TFTP - Trivial File Transfer Protocol

What is TFTP?

TFTP stands for Trivial File Transfer Protocol. It is a simple, lightweight protocol used to transfer files between devices on a network. Unlike FTP, TFTP does not require authentication and is typically used in local or controlled environments.

What is the purpose of TFTP?

• Has a very small footprint, making it ideal for embedded systems.

• Easy to implement and use in bootstrapping and firmware updates.

• Commonly used for network booting, such as loading operating systems or configurations onto routers, switches, or diskless workstations.

How does it work?

• Client sends a request – A device sends a read or write request to the TFTP server.

• Server responds – The server acknowledges and begins the file transfer.

• Data is transferred in blocks – Each block is acknowledged by the receiver.

• Transfer completes – When the last block is received and acknowledged, the session ends.

Where is TFTP used?

• Network booting (PXE) – For loading OS images onto diskless clients.

• Firmware upgrades – For routers, switches, and embedded devices.

• Configuration backups – For network equipment in enterprise environments.

• Embedded systems – Where minimal protocol overhead is needed.

Which OSI Layer does this protocol belong to?

• TFTP operates at the Application Layer (Layer 7) of the OSI model.

• It provides file transfer services directly to applications or users.

• Defines application-level commands like read and write requests.

• Uses UDP (Layer 4) for transport, but protocol logic resides at Layer 7.

Topics in this section,

• Learnings in this section

• Terminology

• Version Info

• TFTP Version&RFC Details

• TFTP Basic Setup on Ubuntu using IPv4

• TFTP Basic Setup on Ubuntu using IPv6

• TFTP Protocol Packet Details

• TFTP Usecases

• TFTP Basic Features

• TFTP Feature : File Transfer

• TFTP Feature : Authentication

• TFTP Feature : Directory Operations

• TFTP Feature : File Management

• TFTP Feature : Modes of Transfer

• TFTP Feature : Transfer Types

• TFTP Feature : Multiple Platforms

• TFTP Feature : Control and Data Channels

• TFTP Feature : Logging and Auditing

• Reference links

Learnings in this section

• In this section, you are going to learn

Terminology

• Terminology

Version Info

• Version Info

TFTP Version&RFC Details

sno	version	RFC - Version	Core / Contribution	Year
1	TFTP v1	RFC 783	Initial specification by Karen R. Sollins	1981
2	TFTP v2	RFC 1350	Revision 2 fixes and clarifications (e.g., Sorcerer’s Apprentice bug)	1992
3	TFTP Option Extension	RFC 1782 (superseded), RFC 2347	Adds option negotiation mechanism	1995 (RFC 1782), 1998 (RFC 2347)

TFTP Basic Setup on Ubuntu using IPv4

• Setup

TFTP Basic Setup on Ubuntu using IPv6

• Setup

TFTP Protocol Packet Details

Read Request (RRQ) Packet

S.No	Protocol Packets	Description	Size(bytes)
1	Read Request (RRQ) Packet	Client requests to read a file from the server	~10-300
	Arguments	Opcode + Filename + Mode	260
	Opcode	1 (RRQ)	1
	Filename	Name of the file to read	variable(255+)
	Mode	Transfer mode (e.g., netascii, octet, mail)	variable(1-10)

Write Request (WRQ) Packet

2	Write Request (WRQ) Packet	Client requests to write a file to the server	~10-300
	Arguments	Opcode + Filename + Mode	260
	Opcode	2 (WRQ)	1
	Filename	Name of the file to write	variable(255+)
	Mode	Transfer mode (e.g., netascii, octet, mail)	variable(1-10)

DATA Packet

3	DATA Packet	Carries a block of file data	4-516
	Arguments	Opcode + Block number	4
	Opcode	3	2
	Block Number	Sequence number of the data block	2
	Data Payload	File Data	variable(0-512)

Acknowledgment (ACK) Packet

4	Acknowledgment (ACK) Packet	Acknowledges receipt of a data block	4
	Arguments	Opcode + Block number	4
	Opcode	4	2
	Block Number	Acknowledges the corresponding data block	2

ERROR Packet

5	ERROR Packet	Indicates an error occurred during transfer	5-260+
	Arguments	Opcode + Error Code	7
	Opcode	5	2
	Error Code	Indicates the type of error (e.g., file not found, access violation)	2
	Error Message	Human-readable error description	variable(1-255+)

Option Acknowledgment (OACK) Packet

6	Option Acknowledgment (OACK) Packet	Acknowledges options in extended TFTP (RFC 2347)	4300+
	Arguments	Opcode+Options	250
	Opcode	6	2
	Options	Option String in format Key-value pairs for options like block size, timeout, etc.	Variable

TFTP Usecases

sno	Use cases	Description
1	Network Booting (PXE Boot)	TFTP is widely used to transfer boot files to diskless workstations or thin clients during Preboot Execution Environment (PXE) booting.
2	Firmware Updates	Many embedded systems (e.g., routers, switches, IoT devices) use TFTP to download firmware updates due to its simplicity and low overhead.
3	Configuration File Transfers	Network devices like switches and routers often use TFTP to upload or download configuration files.
4	Backup and Restore	TFTP can be used to back up or restore device configurations in network management.
5	Simple File Transfers	In controlled environments, TFTP is used for transferring files where authentication and encryption are not required.
6	VoIP Phone Provisioning	TFTP is used to deliver configuration files and firmware to IP phones during provisioning.

TFTP Basic Features

S.no	Feature	Description
1	File Transfer	Simple file transfer without authentication. 2. Mainly used for sending/receiving small files like config files, boot files, etc.
2	Authentication	No, all transfers are unauthenticated and insecure by default.
3	Directory Operations	No support. Can only access files within the server’s root directory.
4	File Management	No support. Only supports upload (WRQ) and download (RRQ) of files.
5	Modes of Transfer	Only uses UDP. No active or passive mode distinction.
6	Transfer Types	Transfers files in octet (binary) or netascii (text) modes. Must be specified at the start of transfer.
7	Multiple Platforms	Supported on most platforms (Linux, Windows, embedded devices, routers, etc.). 2. Command-line tools are common (e.g., tftp, atftp).
8	Control & Data Channels	Uses a single UDP connection (typically port 69 for initial request). 2. Data port negotiated dynamically.
9	Logging & Auditing	Minimal logging support depending on the TFTP server implementation. Basic logs may include IPs, file names, errors.

TFTP Feature : File Transfer

File Transfer - Testcases

S.No	Test Case	Description	Expected Result
1	TC_FT_001	Verify file upload with valid filename	File is uploaded successfully
2	TC_FT_002	Verify file download with valid filename	File is downloaded successfully
3	TC_FT_003	Upload a file that already exists on server	Server overwrites or rejects based on config
4	TC_FT_004	Download a non-existent file	Error message: File not found
5	TC_FT_005	Upload a file with special characters in name	Error or success based on server config
6	TC_FT_006	Upload a file with maximum allowed size	File is uploaded successfully
7	TC_FT_007	Upload a file exceeding maximum size	Error: File too large
8	TC_FT_008	Download a file while another upload is in progress	File is downloaded or queued
9	TC_FT_009	Upload a file with read-only permissions	Error: Permission denied
10	TC_FT_010	Download a file with write-only permissions	Error: Permission denied
11	TC_FT_011	Upload a binary file	File is uploaded and integrity maintained
12	TC_FT_012	Download a binary file	File is downloaded and integrity maintained
13	TC_FT_013	Upload a file with 0 bytes	File is uploaded successfully
14	TC_FT_014	Download a file with 0 bytes	File is downloaded successfully
15	TC_FT_015	Upload a file with long filename (>255 chars)	Error: Filename too long
16	TC_FT_016	Download a file with long filename	Error: Filename too long
17	TC_FT_017	Upload file with invalid characters in name	Error: Invalid filename
18	TC_FT_018	Download file with invalid characters in name	Error: Invalid filename
19	TC_FT_019	Upload file with slow network	File uploads with delay or timeout
20	TC_FT_020	Download file with slow network	File downloads with delay or timeout
21	TC_FT_021	Upload file with packet loss	Retransmission occurs, file uploads
22	TC_FT_022	Download file with packet loss	Retransmission occurs, file downloads
23	TC_FT_023	Upload file with corrupted data	Error or corrupted file on server
24	TC_FT_024	Download file with corrupted data	Error or corrupted file on client
25	TC_FT_025	Upload file with timeout	Error: Timeout occurred
26	TC_FT_026	Download file with timeout	Error: Timeout occurred
27	TC_FT_027	Upload file with duplicate request	Server handles duplicate gracefully
28	TC_FT_028	Download file with duplicate request	Server handles duplicate gracefully
29	TC_FT_029	Upload file with invalid TFTP opcode	Error: Illegal TFTP operation
30	TC_FT_030	Download file with invalid TFTP opcode	Error: Illegal TFTP operation
31	TC_FT_031	Upload file with incorrect block number	Error or retransmission
32	TC_FT_032	Download file with incorrect block number	Error or retransmission
33	TC_FT_033	Upload file with unsupported mode (e.g., “netascii”)	Error: Unsupported mode
34	TC_FT_034	Download file with unsupported mode	Error: Unsupported mode
35	TC_FT_035	Upload file with mode “octet”	File is uploaded successfully
36	TC_FT_036	Download file with mode “octet”	File is downloaded successfully
37	TC_FT_037	Upload file with interrupted connection	Upload fails or resumes if supported
38	TC_FT_038	Download file with interrupted connection	Download fails or resumes if supported
39	TC_FT_039	Upload file with multiple clients	Server handles concurrent uploads
40	TC_FT_040	Download file with multiple clients	Server handles concurrent downloads
41	TC_FT_041	Upload file with invalid server IP	Error: Host unreachable
42	TC_FT_042	Download file with invalid server IP	Error: Host unreachable
43	TC_FT_043	Upload file with firewall blocking port 69	Error: Connection refused
44	TC_FT_044	Download file with firewall blocking port 69	Error: Connection refused
45	TC_FT_045	Upload file with server disk full	Error: Disk full or allocation exceeded
46	TC_FT_046	Download file with client disk full	Error: Disk full
47	TC_FT_047	Upload file with filename case sensitivity	Server handles case as per config
48	TC_FT_048	Download file with filename case sensitivity	Server handles case as per config
49	TC_FT_049	Upload file with retry mechanism	File uploads after retries
50	TC_FT_050	Download file with retry mechanism	File downloads after retries

TFTP Feature : Authentication

Authentication - Testcases

S.No	Test Case	Description	Expected Result
1	Valid Login	Login with correct username and password	Login successful
2	Invalid Username	Login with incorrect username	Authentication fails
3	Invalid Password	Login with incorrect password	Authentication fails
4	Empty Username	Attempt login with empty username	Authentication fails
5	Empty Password	Attempt login with empty password	Authentication fails
6	Both Fields Empty	Attempt login with empty username and password	Authentication fails
7	Case Sensitivity	Login with correct credentials but wrong case	Authentication fails
8	Special Characters in Username	Use special characters in username	Authentication fails or succeeds based on server rules
9	Special Characters in Password	Use special characters in password	Authentication succeeds if password is correct
10	Long Username	Use a very long username	Authentication fails or succeeds based on server limits
11	Long Password	Use a very long password	Authentication fails or succeeds based on server limits
12	SQL Injection Attempt	Try SQL injection in login fields	Authentication fails, input sanitized
13	Anonymous Login Allowed	Login using anonymous credentials	Login successful
14	Anonymous Login Disallowed	Attempt anonymous login when disabled	Authentication fails
15	Login with Expired Account	Use expired user credentials	Authentication fails
16	Login with Locked Account	Use credentials of a locked account	Authentication fails
17	Login with Disabled Account	Use credentials of a disabled account	Authentication fails
18	Login with Inactive Account	Use credentials of an inactive account	Authentication fails
19	Login with Multiple Sessions	Login from multiple clients simultaneously	All sessions authenticated if allowed
20	Login with IP Restriction	Login from unauthorized IP	Authentication fails
21	Login with Time Restriction	Login outside allowed time window	Authentication fails
22	Login with Role Restriction	Login with user not allowed FTP access	Authentication fails
23	Login with Correct Credentials After Failure	Retry login after failed attempt	Login successful
24	Login After Multiple Failures	Login after several failed attempts	Account may be locked or login succeeds
25	Login with Encrypted Password	Use encrypted password (e.g., FTPS)	Authentication successful
26	Login with Plaintext Password	Use plaintext password (FTP)	Authentication successful
27	Login with SFTP	Authenticate using SFTP protocol	Authentication successful
28	Login with FTPS	Authenticate using FTPS protocol	Authentication successful
29	Login with Invalid Port	Attempt login on wrong port	Connection fails
30	Login with Correct Port	Attempt login on correct port	Authentication successful
31	Login with Proxy	Authenticate via FTP proxy	Authentication successful
32	Login with VPN	Authenticate via VPN connection	Authentication successful
33	Login with Firewall Enabled	Authenticate with firewall restrictions	Authentication may fail or succeed
34	Login with Brute Force Attempt	Simulate brute force login	Account locked or blocked
35	Login with Captcha (if enabled)	Attempt login with captcha	Authentication succeeds if captcha passed
36	Login with MFA Enabled	Authenticate with multi-factor authentication	Authentication successful
37	Login with MFA Disabled	Authenticate without MFA	Authentication successful
38	Login with Certificate	Authenticate using client certificate	Authentication successful
39	Login with Invalid Certificate	Use invalid certificate	Authentication fails
40	Login with Expired Certificate	Use expired certificate	Authentication fails
41	Login with Revoked Certificate	Use revoked certificate	Authentication fails
42	Login with Public Key	Authenticate using SSH public key	Authentication successful
43	Login with Invalid Public Key	Use wrong public key	Authentication fails
44	Login with Password Policy Violation	Use password not meeting policy	Authentication fails
45	Login with Session Timeout	Login after session timeout	Re-authentication required
46	Login with Session Persistence	Maintain session after login	Session remains active
47	Login with Session Hijacking Attempt	Simulate session hijack	Session invalidated
48	Login with Logging Enabled	Enable logging during login	Login attempts logged
49	Login with Audit Trail	Ensure audit trail is recorded	Login recorded in audit logs
50	Login with Server Restart	Attempt login after server restart	Authentication successful

TFTP Feature : Directory Operations

Directory Operations - Testcases

S.No	Test Case	Description	Expected Result
1	TC_DIR_001	List contents of a valid directory	Directory contents listed
2	TC_DIR_002	List contents of an empty directory	Message: Directory is empty
3	TC_DIR_003	List contents of a non-existent directory	Error: Directory not found
4	TC_DIR_004	Create a new directory with valid name	Directory created successfully
5	TC_DIR_005	Create a directory that already exists	Error: Directory already exists
6	TC_DIR_006	Create directory with special characters	Error or sanitized name
7	TC_DIR_007	Create directory with long name (>255 chars)	Error: Name too long
8	TC_DIR_008	Delete an existing empty directory	Directory deleted successfully
9	TC_DIR_009	Delete a non-empty directory	Error or recursive delete based on config
10	TC_DIR_010	Delete a non-existent directory	Error: Directory not found
11	TC_DIR_011	Rename a directory with valid new name	Directory renamed successfully
12	TC_DIR_012	Rename a directory to an existing name	Error: Name conflict
13	TC_DIR_013	Rename a non-existent directory	Error: Directory not found
14	TC_DIR_014	Navigate to a valid subdirectory	Navigation successful
15	TC_DIR_015	Navigate to a non-existent subdirectory	Error: Directory not found
16	TC_DIR_016	Navigate using relative path	Navigation successful
17	TC_DIR_017	Navigate using absolute path	Navigation successful
18	TC_DIR_018	Navigate using “..” to parent directory	Navigation successful
19	TC_DIR_019	Attempt directory traversal attack	Error: Access denied
20	TC_DIR_020	List directory with read-only permissions	Directory listed
21	TC_DIR_021	Create directory with write-only permissions	Error: Permission denied
22	TC_DIR_022	Delete directory with insufficient permissions	Error: Permission denied
23	TC_DIR_023	List directory with special characters in path	Error or sanitized path
24	TC_DIR_024	Create nested directories in one command	Directories created recursively
25	TC_DIR_025	Delete nested directories recursively	All directories deleted
26	TC_DIR_026	List directory with symbolic link	Target directory listed
27	TC_DIR_027	Create directory with symbolic link in path	Directory created at target
28	TC_DIR_028	Delete directory with symbolic link	Target directory deleted
29	TC_DIR_029	List directory with large number of files	All files listed
30	TC_DIR_030	List directory with timeout	Error: Timeout occurred
31	TC_DIR_031	Create directory with timeout	Error: Timeout occurred
32	TC_DIR_032	Delete directory with timeout	Error: Timeout occurred
33	TC_DIR_033	List directory with network interruption	Error or retry
34	TC_DIR_034	Create directory with network interruption	Error or retry
35	TC_DIR_035	Delete directory with network interruption	Error or retry
36	TC_DIR_036	List directory with invalid characters in path	Error: Invalid path
37	TC_DIR_037	Create directory with invalid characters	Error: Invalid name
38	TC_DIR_038	Delete directory with invalid characters	Error: Invalid name
39	TC_DIR_039	List directory with symbolic link loop	Error: Loop detected
40	TC_DIR_040	Create directory with trailing slash	Directory created successfully
41	TC_DIR_041	Delete directory with trailing slash	Directory deleted successfully
42	TC_DIR_042	List directory with trailing slash	Directory listed
43	TC_DIR_043	Attempt to create directory in restricted path	Error: Access denied
44	TC_DIR_044	Attempt to delete root directory	Error: Operation not allowed
45	TC_DIR_045	Attempt to rename root directory	Error: Operation not allowed
46	TC_DIR_046	Attempt to list root directory	Root directory listed
47	TC_DIR_047	Attempt to create directory with unicode characters	Directory created successfully
48	TC_DIR_048	Attempt to list directory with unicode characters	Directory listed successfully
49	TC_DIR_049	Attempt to delete directory with unicode characters	Directory deleted successfully
50	TC_DIR_050	Attempt to perform directory operations without authentication	Error: Authentication required

TFTP Feature : File Management

File Management - Testcases

S.No	Test Case	Description	Expected Result
1	TC_FM_001	Upload a file to the server	File uploaded successfully
2	TC_FM_002	Download a file from the server	File downloaded successfully
3	TC_FM_003	Delete an existing file	File deleted successfully
4	TC_FM_004	Delete a non-existent file	Error: File not found
5	TC_FM_005	Rename a file with a valid new name	File renamed successfully
6	TC_FM_006	Rename a file to an existing filename	Error: File already exists
7	TC_FM_007	Rename a non-existent file	Error: File not found
8	TC_FM_008	Move a file to a different directory	File moved successfully
9	TC_FM_009	Move a file to a non-existent directory	Error: Directory not found
10	TC_FM_010	Copy a file to another location	File copied successfully
11	TC_FM_011	Copy a file with overwrite disabled	Error: File already exists
12	TC_FM_012	Overwrite an existing file during upload	File overwritten successfully
13	TC_FM_013	Attempt to delete a file without permission	Error: Permission denied
14	TC_FM_014	Attempt to rename a file without permission	Error: Permission denied
15	TC_FM_015	Attempt to move a file without permission	Error: Permission denied
16	TC_FM_016	Attempt to copy a file without permission	Error: Permission denied
17	TC_FM_017	Upload a file with special characters in name	File uploaded or sanitized
18	TC_FM_018	Delete a file with special characters in name	File deleted or error
19	TC_FM_019	Rename a file with special characters	File renamed or error
20	TC_FM_020	Upload a file with long filename (>255 chars)	Error: Filename too long
21	TC_FM_021	Delete a file with long filename	Error: Filename too long
22	TC_FM_022	Rename a file with long filename	Error: Filename too long
23	TC_FM_023	Upload a file with unicode characters	File uploaded successfully
24	TC_FM_024	Delete a file with unicode characters	File deleted successfully
25	TC_FM_025	Rename a file with unicode characters	File renamed successfully
26	TC_FM_026	Upload a file with read-only permissions	Error: Permission denied
27	TC_FM_027	Delete a file with read-only permissions	Error: Permission denied
28	TC_FM_028	Rename a file with read-only permissions	Error: Permission denied
29	TC_FM_029	Move a file with read-only permissions	Error: Permission denied
30	TC_FM_030	Upload a file with write-only permissions	File uploaded successfully
31	TC_FM_031	Attempt to delete a file during transfer	Error or operation queued
32	TC_FM_032	Attempt to rename a file during transfer	Error or operation queued
33	TC_FM_033	Attempt to move a file during transfer	Error or operation queued
34	TC_FM_034	Attempt to copy a file during transfer	Error or operation queued
35	TC_FM_035	Upload a file with same name but different case	File uploaded or conflict based on case sensitivity
36	TC_FM_036	Delete a file with same name but different case	File deleted or not found
37	TC_FM_037	Rename a file to same name with different case	File renamed or error
38	TC_FM_038	Upload a file with invalid characters	Error: Invalid filename
39	TC_FM_039	Delete a file with invalid characters	Error: Invalid filename
40	TC_FM_040	Rename a file with invalid characters	Error: Invalid filename
41	TC_FM_041	Upload a file to a restricted directory	Error: Access denied
42	TC_FM_042	Delete a file from a restricted directory	Error: Access denied
43	TC_FM_043	Rename a file in a restricted directory	Error: Access denied
44	TC_FM_044	Move a file from a restricted directory	Error: Access denied
45	TC_FM_045	Copy a file from a restricted directory	Error: Access denied
46	TC_FM_046	Upload a file with network interruption	Upload fails or retries
47	TC_FM_047	Delete a file with network interruption	Operation fails or retries
48	TC_FM_048	Rename a file with network interruption	Operation fails or retries
49	TC_FM_049	Move a file with network interruption	Operation fails or retries
50	TC_FM_050	Copy a file with network interruption	Operation fails or retries

TFTP Feature : Modes of Transfer

Modes of Transfer - Testcases

S.No	Test Case	Description	Expected Result
1	TC_MODE_001	Upload file using octet mode	File uploaded successfully
2	TC_MODE_002	Download file using octet mode	File downloaded successfully
3	TC_MODE_003	Upload file using netascii mode	File uploaded with correct text formatting
4	TC_MODE_004	Download file using netascii mode	File downloaded with correct text formatting
5	TC_MODE_005	Upload binary file using octet mode	File integrity maintained
6	TC_MODE_006	Upload binary file using netascii mode	File corrupted due to mode mismatch
7	TC_MODE_007	Download binary file using octet mode	File integrity maintained
8	TC_MODE_008	Download binary file using netascii mode	File corrupted due to mode mismatch
9	TC_MODE_009	Upload text file using netascii mode	File uploaded with correct line endings
10	TC_MODE_010	Download text file using netascii mode	File downloaded with correct line endings
11	TC_MODE_011	Upload text file using octet mode	File uploaded as-is
12	TC_MODE_012	Download text file using octet mode	File downloaded as-is
13	TC_MODE_013	Upload file with invalid mode	Error: Unsupported transfer mode
14	TC_MODE_014	Download file with invalid mode	Error: Unsupported transfer mode
15	TC_MODE_015	Upload file with mode in uppercase (OCTET)	File uploaded successfully
16	TC_MODE_016	Download file with mode in uppercase (NETASCII)	File downloaded successfully
17	TC_MODE_017	Upload file with mixed-case mode (Octet)	File uploaded successfully
18	TC_MODE_018	Download file with mixed-case mode (NetAscii)	File downloaded successfully
19	TC_MODE_019	Upload file with empty mode field	Error: Mode not specified
20	TC_MODE_020	Download file with empty mode field	Error: Mode not specified
21	TC_MODE_021	Upload file with whitespace in mode	Error: Invalid mode
22	TC_MODE_022	Download file with whitespace in mode	Error: Invalid mode
23	TC_MODE_023	Upload file with mode set to “mail”	Error or ignored (deprecated)
24	TC_MODE_024	Download file with mode set to “mail”	Error or ignored (deprecated)
25	TC_MODE_025	Upload file with mode set to null	Error: Mode not specified
26	TC_MODE_026	Download file with mode set to null	Error: Mode not specified
27	TC_MODE_027	Upload file with mode set to binary (alias for octet)	File uploaded successfully (if supported)
28	TC_MODE_028	Download file with mode set to binary	File downloaded successfully (if supported)
29	TC_MODE_029	Upload file with mode set to text (alias for netascii)	File uploaded successfully (if supported)
30	TC_MODE_030	Download file with mode set to text	File downloaded successfully (if supported)
31	TC_MODE_031	Upload file with mode set to unsupported value	Error: Unsupported mode
32	TC_MODE_032	Download file with mode set to unsupported value	Error: Unsupported mode
33	TC_MODE_033	Upload file with mode set to numeric value	Error: Invalid mode
34	TC_MODE_034	Download file with mode set to numeric value	Error: Invalid mode
35	TC_MODE_035	Upload file with mode set to special characters	Error: Invalid mode
36	TC_MODE_036	Download file with mode set to special characters	Error: Invalid mode
37	TC_MODE_037	Upload file with mode set to null byte	Error: Invalid mode
38	TC_MODE_038	Download file with mode set to null byte	Error: Invalid mode
39	TC_MODE_039	Upload file with mode field omitted	Error: Mode not specified
40	TC_MODE_040	Download file with mode field omitted	Error: Mode not specified
41	TC_MODE_041	Upload file with mode field after filename	File uploaded successfully
42	TC_MODE_042	Download file with mode field after filename	File downloaded successfully
43	TC_MODE_043	Upload file with mode field before filename	Error: Invalid request format
44	TC_MODE_044	Download file with mode field before filename	Error: Invalid request format
45	TC_MODE_045	Upload file with mode field in mixed encoding	Error: Invalid mode
46	TC_MODE_046	Download file with mode field in mixed encoding	Error: Invalid mode
47	TC_MODE_047	Upload file with mode field in UTF-8	File uploaded successfully
48	TC_MODE_048	Download file with mode field in UTF-8	File downloaded successfully
49	TC_MODE_049	Upload file with mode field in ASCII	File uploaded successfully
50	TC_MODE_050	Download file with mode field in ASCII	File downloaded successfully

TFTP Feature : Transfer Types

Transfer Types - Testcases

S.No	Test Case	Description	Expected Result
1	TC_TT_001	Send a Read Request (RRQ) for a valid file	File downloaded successfully
2	TC_TT_002	Send a Write Request (WRQ) for a valid file	File uploaded successfully
3	TC_TT_003	Send RRQ for a non-existent file	Error: File not found
4	TC_TT_004	Send WRQ for a file that already exists	File overwritten or error based on config
5	TC_TT_005	Send RRQ with invalid filename	Error: Invalid filename
6	TC_TT_006	Send WRQ with invalid filename	Error: Invalid filename
7	TC_TT_007	Send RRQ with empty filename	Error: Filename required
8	TC_TT_008	Send WRQ with empty filename	Error: Filename required
9	TC_TT_009	Send RRQ with unsupported mode	Error: Unsupported transfer mode
10	TC_TT_010	Send WRQ with unsupported mode	Error: Unsupported transfer mode
11	TC_TT_011	Send RRQ with valid octet mode	File downloaded in binary format
12	TC_TT_012	Send WRQ with valid netascii mode	File uploaded in text format
13	TC_TT_013	Send RRQ with uppercase mode (OCTET)	File downloaded successfully
14	TC_TT_014	Send WRQ with mixed-case mode (NetAscii)	File uploaded successfully
15	TC_TT_015	Send RRQ with invalid opcode	Error: Illegal TFTP operation
16	TC_TT_016	Send WRQ with invalid opcode	Error: Illegal TFTP operation
17	TC_TT_017	Send RRQ with duplicate request	Server handles duplicate gracefully
18	TC_TT_018	Send WRQ with duplicate request	Server handles duplicate gracefully
19	TC_TT_019	Send RRQ with timeout	Error: Timeout occurred
20	TC_TT_020	Send WRQ with timeout	Error: Timeout occurred
21	TC_TT_021	Send RRQ with packet loss	Retransmission occurs, file downloaded
22	TC_TT_022	Send WRQ with packet loss	Retransmission occurs, file uploaded
23	TC_TT_023	Send RRQ with corrupted packet	Error: Invalid packet
24	TC_TT_024	Send WRQ with corrupted packet	Error: Invalid packet
25	TC_TT_025	Send RRQ with large file	File downloaded in multiple blocks
26	TC_TT_026	Send WRQ with large file	File uploaded in multiple blocks
27	TC_TT_027	Send RRQ with block size option	File downloaded with specified block size
28	TC_TT_028	Send WRQ with block size option	File uploaded with specified block size
29	TC_TT_029	Send RRQ with timeout option	File downloaded with custom timeout
30	TC_TT_030	Send WRQ with timeout option	File uploaded with custom timeout
31	TC_TT_031	Send RRQ with transfer size option	Transfer size acknowledged
32	TC_TT_032	Send WRQ with transfer size option	Transfer size acknowledged
33	TC_TT_033	Send RRQ with unsupported option	Error: Option not supported
34	TC_TT_034	Send WRQ with unsupported option	Error: Option not supported
35	TC_TT_035	Send RRQ with option negotiation	Options negotiated successfully
36	TC_TT_036	Send WRQ with option negotiation	Options negotiated successfully
37	TC_TT_037	Attempt to resume interrupted RRQ (if supported)	File resumes download
38	TC_TT_038	Attempt to resume interrupted WRQ (if supported)	File resumes upload
39	TC_TT_039	Attempt to append to file using WRQ (if supported)	Data appended successfully
40	TC_TT_040	Attempt to append to file using unsupported server	Error: Operation not supported
41	TC_TT_041	Attempt to broadcast file using RRQ (if supported)	File broadcasted to multiple clients
42	TC_TT_042	Attempt to broadcast file using WRQ (if supported)	File broadcasted to multiple servers
43	TC_TT_043	Send RRQ with filename containing path traversal	Error: Access denied
44	TC_TT_044	Send WRQ with filename containing path traversal	Error: Access denied
45	TC_TT_045	Send RRQ with symbolic link in filename	File resolved and downloaded
46	TC_TT_046	Send WRQ with symbolic link in filename	File resolved and uploaded
47	TC_TT_047	Send RRQ with filename containing unicode	File downloaded successfully
48	TC_TT_048	Send WRQ with filename containing unicode	File uploaded successfully
49	TC_TT_049	Send RRQ with filename in restricted directory	Error: Access denied
50	TC_TT_050	Send WRQ with filename in restricted directory	Error: Access denied

TFTP Feature : Multiple Platforms

Multiple Platforms - Testcases

S.No	Test Case	Description	Expected Result
1	TC_MP_001	Upload file from Windows client to Linux server	File uploaded successfully
2	TC_MP_002	Download file from Linux server to Windows client	File downloaded successfully
3	TC_MP_003	Upload file from Linux client to Windows server	File uploaded successfully
4	TC_MP_004	Download file from Windows server to Linux client	File downloaded successfully
5	TC_MP_005	Upload file from macOS client to Linux server	File uploaded successfully
6	TC_MP_006	Download file from Linux server to macOS client	File downloaded successfully
7	TC_MP_007	Upload file from embedded device to Linux server	File uploaded successfully
8	TC_MP_008	Download file from Linux server to embedded device	File downloaded successfully
9	TC_MP_009	Upload file from Android client to Windows server	File uploaded successfully
10	TC_MP_010	Download file from Windows server to Android client	File downloaded successfully
11	TC_MP_011	Upload file from iOS client to Linux server	File uploaded successfully
12	TC_MP_012	Download file from Linux server to iOS client	File downloaded successfully
13	TC_MP_013	Upload file from Windows client with long filename	File uploaded or error based on OS
14	TC_MP_014	Upload file from Linux client with case-sensitive name	File uploaded with exact name
15	TC_MP_015	Upload file from Windows client with case-insensitive name	File uploaded, overwrites if name matches
16	TC_MP_016	Upload file from macOS client with special characters	File uploaded or sanitized
17	TC_MP_017	Upload file from Linux client with symbolic link	File or target uploaded based on config
18	TC_MP_018	Upload file from embedded system with limited memory	File uploaded or error: insufficient memory
19	TC_MP_019	Upload file from Android with restricted permissions	Error: Permission denied
20	TC_MP_020	Upload file from iOS with sandboxed file access	Error or success based on app permissions
21	TC_MP_021	Download file to Windows with read-only directory	Error: Access denied
22	TC_MP_022	Download file to Linux with full permissions	File downloaded successfully
23	TC_MP_023	Download file to macOS with firewall enabled	File downloaded or blocked
24	TC_MP_024	Upload file from Windows with antivirus active	File uploaded or scanned
25	TC_MP_025	Upload file from Linux with SELinux enabled	File uploaded or blocked
26	TC_MP_026	Upload file from macOS with Gatekeeper enabled	File uploaded successfully
27	TC_MP_027	Upload file from Android with background data disabled	Error: Network unavailable
28	TC_MP_028	Upload file from iOS with low power mode	File uploaded with delay
29	TC_MP_029	Upload file from Windows with IPv6	File uploaded successfully
30	TC_MP_030	Upload file from Linux with IPv6	File uploaded successfully
31	TC_MP_031	Upload file from macOS with IPv6	File uploaded successfully
32	TC_MP_032	Upload file from embedded system using serial-over-IP	File uploaded successfully
33	TC_MP_033	Upload file from Android using Wi-Fi	File uploaded successfully
34	TC_MP_034	Upload file from iOS using mobile data	File uploaded successfully
35	TC_MP_035	Upload file from Windows using VPN	File uploaded successfully
36	TC_MP_036	Upload file from Linux using proxy	File uploaded or blocked
37	TC_MP_037	Upload file from macOS using corporate network	File uploaded successfully
38	TC_MP_038	Upload file from embedded system with static IP	File uploaded successfully
39	TC_MP_039	Upload file from Android with dynamic IP	File uploaded successfully
40	TC_MP_040	Upload file from iOS with roaming enabled	File uploaded successfully
41	TC_MP_041	Upload file from Windows with TFTP client CLI	File uploaded successfully
42	TC_MP_042	Upload file from Linux using tftp command	File uploaded successfully
43	TC_MP_043	Upload file from macOS using GUI client	File uploaded successfully
44	TC_MP_044	Upload file from Android using TFTP app	File uploaded successfully
45	TC_MP_045	Upload file from iOS using TFTP app	File uploaded successfully
46	TC_MP_046	Upload file from Windows with PowerShell script	File uploaded successfully
47	TC_MP_047	Upload file from Linux with automated cron job	File uploaded successfully
48	TC_MP_048	Upload file from macOS with Automator script	File uploaded successfully
49	TC_MP_049	Upload file from embedded system with firmware TFTP client	File uploaded successfully
50	TC_MP_050	Upload file from Android with custom TFTP library	File uploaded successfully

TFTP Feature : Control and Data Channels

Control and Data Channels - Testcases

S.No	Test Case	Description	Expected Result
1	TC_CD_001	Initiate RRQ on port 69	Server responds with data port
2	TC_CD_002	Initiate WRQ on port 69	Server responds with data port
3	TC_CD_003	Send data to server-assigned port	Data accepted
4	TC_CD_004	Send data to port 69 after initial request	Error: Unexpected port
5	TC_CD_005	Receive data from server-assigned port	Data received successfully
6	TC_CD_006	Receive data from unexpected port	Error: Unknown transfer ID
7	TC_CD_007	Attempt to use same port for multiple transfers	Error or session conflict
8	TC_CD_008	Attempt to use different control and data ports	Transfer proceeds correctly
9	TC_CD_009	Monitor port 69 for control messages only	Only initial requests received
10	TC_CD_010	Monitor dynamic port for data packets	Data packets received
11	TC_CD_011	Send ACK to correct data port	ACK accepted
12	TC_CD_012	Send ACK to incorrect port	Error: Unknown transfer ID
13	TC_CD_013	Simulate port conflict on server	Server handles or rejects session
14	TC_CD_014	Simulate port conflict on client	Client handles or retries
15	TC_CD_015	Send RRQ from non-standard client port	Server responds correctly
16	TC_CD_016	Send WRQ from non-standard client port	Server responds correctly
17	TC_CD_017	Use firewall to block port 69	Initial request fails
18	TC_CD_018	Use firewall to block data port	Transfer fails mid-session
19	TC_CD_019	Use NAT between client and server	Transfer succeeds with correct mapping
20	TC_CD_020	Use proxy between client and server	Transfer succeeds if proxy supports UDP
21	TC_CD_021	Monitor session for port reuse	Ports are unique per session
22	TC_CD_022	Attempt to hijack session using spoofed port	Error: Unknown transfer ID
23	TC_CD_023	Attempt to inject data from unauthorized port	Data rejected
24	TC_CD_024	Attempt to send ACK from unauthorized port	ACK rejected
25	TC_CD_025	Simulate timeout on control port	Session fails to start
26	TC_CD_026	Simulate timeout on data port	Transfer interrupted
27	TC_CD_027	Simulate packet loss on control port	Request retransmitted
28	TC_CD_028	Simulate packet loss on data port	Data retransmitted
29	TC_CD_029	Use IPv6 for control and data ports	Transfer succeeds
30	TC_CD_030	Use IPv4 for control and data ports	Transfer succeeds
31	TC_CD_031	Use mixed IPv4/IPv6 endpoints	Transfer fails or adapts
32	TC_CD_032	Use same port for control and data (non-standard)	Transfer fails or succeeds based on implementation
33	TC_CD_033	Log control and data port usage	Ports logged correctly
34	TC_CD_034	Attempt to change data port mid-transfer	Transfer fails
35	TC_CD_035	Attempt to change control port mid-transfer	Transfer fails
36	TC_CD_036	Use encrypted tunnel for control port	Control request secured
37	TC_CD_037	Use encrypted tunnel for data port	Data secured
38	TC_CD_038	Use VPN for both control and data	Transfer succeeds
39	TC_CD_039	Use different interfaces for control and data	Transfer succeeds if routing is correct
40	TC_CD_040	Use same interface for multiple sessions	All sessions succeed
41	TC_CD_041	Simulate DoS on control port	New sessions blocked
42	TC_CD_042	Simulate DoS on data port	Active transfers disrupted
43	TC_CD_043	Monitor port usage during concurrent transfers	Unique ports used
44	TC_CD_044	Attempt to reuse data port after session ends	Port reused safely
45	TC_CD_045	Attempt to reuse control port after session ends	Port reused safely
46	TC_CD_046	Use ephemeral ports for data transfer	Transfer succeeds
47	TC_CD_047	Use fixed port for data transfer (non-standard)	Transfer fails or succeeds based on config
48	TC_CD_048	Attempt to bind to port 69 without privileges	Error: Permission denied
49	TC_CD_049	Attempt to bind to data port already in use	Error or port reassigned
50	TC_CD_050	Verify port closure after transfer completion	Ports released successfully

TFTP Feature : Logging and Auditing

Logging and Auditing - Testcases

S.No	Test Case	Description	Expected Result
1	Log_Test_01	Verify logging for successful download by anonymous user	Log includes timestamp, IP, filename, operation=download, status=success, user=anon
2	Log_Test_02	Verify logging for failed upload due to permission error	Log includes timestamp, IP, filename, operation=upload, status=failure, error=403
3	Log_Test_03	Verify logging for timeout during file transfer	Log includes timestamp, IP, filename, operation, status=timeout
4	Log_Test_04	Verify logging for malformed TFTP request	Log includes timestamp, IP, operation=unknown, status=error, error=malformed packet
5	Log_Test_05	Verify logging for successful upload by authenticated user	Log includes timestamp, IP, filename, operation=upload, status=success, user=auth
6	Log_Test_06	Verify logging for download with interrupted session	Log includes timestamp, IP, filename, operation=download, status=interrupted
7	Log_Test_07	Verify logging for upload with invalid file format	Log includes timestamp, IP, filename, operation=upload, status=error, error=format
8	Log_Test_08	Verify logging for retry after failed upload	Log includes retry count, timestamp, status=retry
9	Log_Test_09	Verify logging for download from restricted directory	Log includes timestamp, IP, status=denied, error=restricted access
10	Log_Test_10	Verify logging for upload with large file size	Log includes timestamp, IP, filename, size, status=success
11	Log_Test_11	Verify logging for download with checksum verification	Log includes checksum, status=verified
12	Log_Test_12	Verify logging for upload with checksum mismatch	Log includes checksum, status=error, error=checksum mismatch
13	Log_Test_13	Verify logging for anonymous upload attempt	Log includes user=anonymous, status=denied
14	Log_Test_14	Verify logging for authenticated download	Log includes user=authenticated, status=success
15	Log_Test_15	Verify logging for session timeout	Log includes session ID, status=timeout
16	Log_Test_16	Verify logging for duplicate upload request	Log includes duplicate flag, status=ignored
17	Log_Test_17	Verify logging for download with invalid filename	Log includes filename, status=error, error=invalid name
18	Log_Test_18	Verify logging for upload with special characters	Log includes filename, status=success
19	Log_Test_19	Verify logging for download with throttled bandwidth	Log includes bandwidth info, status=success
20	Log_Test_20	Verify logging for upload with network failure	Log includes error=network failure, status=error
21	Log_Test_21	Verify logging for download with expired token	Log includes token status=expired, status=denied
22	Log_Test_22	Verify logging for upload with valid token	Log includes token status=valid, status=success
23	Log_Test_23	Verify logging for download with IP filtering	Log includes IP, status=blocked if not allowed
24	Log_Test_24	Verify logging for upload with IP whitelisting	Log includes IP, status=allowed
25	Log_Test_25	Verify logging for download with session reuse	Log includes session ID, reuse=true
26	Log_Test_26	Verify logging for upload with session expiration	Log includes session ID, status=expired
27	Log_Test_27	Verify logging for download with multiple retries	Log includes retry count, status=success
28	Log_Test_28	Verify logging for upload with partial success	Log includes status=partial, bytes transferred
29	Log_Test_29	Verify logging for download with user-agent info	Log includes user-agent string
30	Log_Test_30	Verify logging for upload with client version info	Log includes client version, status=success
31	Log_Test_31	Verify logging for download with audit trail ID	Log includes audit ID, status=success
32	Log_Test_32	Verify logging for upload with audit trail ID	Log includes audit ID, status=success
33	Log_Test_33	Verify logging for download with encryption enabled	Log includes encryption=true, status=success
34	Log_Test_34	Verify logging for upload with encryption disabled	Log includes encryption=false, status=success
35	Log_Test_35	Verify logging for download with file not found	Log includes status=error, error=file not found
36	Log_Test_36	Verify logging for upload with permission granted	Log includes permission=granted, status=success
37	Log_Test_37	Verify logging for download with permission denied	Log includes permission=denied, status=error
38	Log_Test_38	Verify logging for upload with audit log disabled	Log includes audit=disabled, status=warning
39	Log_Test_39	Verify logging for download with audit log enabled	Log includes audit=enabled, status=success
40	Log_Test_40	Verify logging for upload with invalid session ID	Log includes session ID, status=error, error=invalid session
41	Log_Test_41	Verify logging for download with valid session ID	Log includes session ID, status=success
42	Log_Test_42	Verify logging for upload with file overwrite	Log includes overwrite=true, status=success
43	Log_Test_43	Verify logging for download with file versioning	Log includes version info, status=success
44	Log_Test_44	Verify logging for upload with file version conflict	Log includes version conflict, status=error
45	Log_Test_45	Verify logging for download with access log rotation	Log includes log rotation event, status=success
46	Log_Test_46	Verify logging for upload with access log rotation	Log includes log rotation event, status=success
47	Log_Test_47	Verify logging for download with audit timestamp accuracy	Log includes timestamp with millisecond precision
48	Log_Test_48	Verify logging for upload with audit timestamp accuracy	Log includes timestamp with millisecond precision
49	Log_Test_49	Verify logging for download with concurrent sessions	Log includes session count, status=success
50	Log_Test_50	Verify logging for upload with concurrent sessions	Log includes session count, status=success

Reference links

• Reference links