Encryption Control Protocol
The Encryption Control Protocol ( ECP for short ) is a network protocol . It enables encryption with PPP (Point-to-Point Protocol). For example, Triple DES encryption is implemented using 3DESE (Triple DES Encryption Protocol Extension) .
The same packet exchange method is used as with the LCP (Link Control Protocol). ECP packets may not be able to be exchanged until PPP has reached the network layer protocol phase. The received ECP packets should always be discarded before this happens.
ECP header
| ECP header (Encryption Control Protocol) | |||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4th | 5 | 6th | 7th | 8th | 9 | 10 | 11 | 12 | 13 | 14th | 15th | 16 | 17th | 18th | 19th | 20th | 21st | 22nd | 23 | 24 | 25th | 26th | 27 | 28 | 29 | 30th | 31 |
| Code (code) |
Identifier (identifier) |
Length (length) |
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| Data (data) |
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Code Description Reference
The code is 8 bits. Specifies the function to be performed.
| code | description | reference |
|---|---|---|
| 0 | Vendor Specific. | RFC 2153 |
| 1 | Configure request. | |
| 2 | Configure-Ack. | |
| 3 | Configure-Nak. | |
| 4th | Configure-Reject. | |
| 5 | Terminate request. | |
| 6th | Terminate-Ack. | |
| 7th | Code reject. | |
| 8-13 | ||
| 14th | Reset request. | RFC 1968 |
| 15th | Reset Ack. | RFC 1968 |
The identifier is 8 bits . Is used to control the requests and responses.
The length is 16 bits. Size of the package including the header.
The data has a variable length. Zero or more bytes of data is described by the length field. This field contains one or more options.
ECP configuration options
| ECP configuration options | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4th | 5 | 6th | 7th | 8th | 9 | 10 | 11 | 12 | 13 | 14th | 15th |
| Option (options) |
Length (length) |
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| Data (data) |
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The option is 8 bits.
| option | Length | description | reference |
|---|---|---|---|
| 0 | > = 6 | OUI, Organizationally Unique Identifier. | RFC 1968 |
| 1 | 10 | DESE, PPP DES Encryption Protocol. (Deprecated). | RFC 1969 |
| 2 | 10 | 3DESE, PPP Triple-DES Encryption Protocol. | RFC 2420 |
| 3 | 10 | DESE-bis, PPP DES Data Encryption Standard Protocol. | RFC 2419 |
| 4-255 |
The length is 8 bits. The data has a variable length.