Configure DLC

Realization information

Tast list of DLC configuration

Example of configuration

Realization information

 DLC module is designed to make better use of bandwidth. By applying the functionality of DLC, the information data encapsulated in data link layer protocol such as PPP Protocol, can be compressed by the DLC module before being sent to physical layer for transmission; Or the compressed data in information field of packet received from physical layer can be decompressed by the DLC module before being delivered to network layer. PPP protocol is supported by such module for compression data transmission. Lempel-Ziv(compatible with STAC LZS) compression protocol and MPPC compression protocol have been implemented. All the physic or logical interface that can be encapsulated with PPP protocol, can be configured with compression protocol. Generally speaking, the ratio of compression will be 2:1.

 

Tast list of DLC configuration

The configuration step that configure compression protocol for interface is below

step

command

function

1

Encapsulation PPP

Encapsulation PPP protocol(note 1)

2

Dlc-compress Lempel-Ziv | MPPC

Configure compression protocol (note 2)

Note 1: First enter interface configuration mode and encapsulated PPP Protocol. Assure CCP Protocol has been implementedRFC1962

Note 2: Select one kind of compression protocol from Lempel-Ziv and MPPC. Assure that both two terminals of the PPP connection are configured the same compression protocol.

 

Example of configuration

Suppose that router A and B are available. A is D-Link Router,B is CISCO routerA and B are connected by synchro serial line. Suppose that one serial interface number of A is S2/0:1one serial interface number of B is S1/:1; Both two interfaces are encapsulated by PPP protocol.CCP protocolRFC1962is implemented in software module of the two routers

 

If configured with Lempel-Ziv(STAC LZS) compression, basic configurations of the two interfaces are as below

 

A)      Serial interface S2/0:1of D-Link is configured as :

interface Serial/:

  ip address 18.0.0.1 255.255.255.0

no ip directed-broadcast

  encapsulation ppp

bandwidth 64

dlc-compress Lempel-Ziv

B)      Serial interface S1/0:0 of CISCO is configured as:

interface Serial1/1:

  ip address 18.0.0.2 255.255.255.0

  encapsulation ppp

compress stac

 

 

If configured with MPPC compression protocol, basic configurations of the two interfaces are as below

 

A)      Serial interface S2/0:1of D-Link is configured as :

interface Serial/:

  ip address 18.0.0.1 255.255.255.0

no ip directed-broadcast

  encapsulation ppp

bandwidth 64

dlc-compress MPPC

B)      Serial interface S1/0:0 of CISCO is configured as:

interface Serial1/1:

  ip address 18.0.0.2 255.255.255.0

  encapsulation ppp

compress MPPC