Specifications

Specify HSSI Encapsulation
Configuring Serial Interfaces IC-69
Specify HSSI Encapsulation
The HSSI supports the serial encapsulation methods, except for X.25-based encapsulations. The
default method is HDLC. You can define the encapsulation method by using the following command
in interface configuration mode:
For information about PPP, see the “Configuring Asynchronous PPP and SLIP” and “Configuring
Media-Independent PPP and Multilink PPP” chapters in the Dial Solutions Configuration Guide.
Invoke ATM on a HSSI Line
If you have an ATM DSU, you can invoke ATM over a HSSI line. You do so by mapping an ATM
virtual path identifier (VPI) and virtual channel identifier (VCI) to a DXI frame address. ATM-DXI
encapsulation defines a data exchange interface that allows a DTE (such as a router) and a DCE (such
as an ATM DSU) to cooperate to provide a User-Network Interface (UNI) for ATM networks.
To invoke ATM over a serial line, use the following commands in interface configuration mode:
You can also configure the dxi map command on a serial interface.
To configure an ATM interface using an AIP card, see the “Configuring ATM” chapter in the
Wide-Area Networking Configuration Guide.
Convert HSSI to Clock Master
HSSI network module provides full-duplex connectivity at Synchronous Optical Network (SONET)
OC-1/STS-1 (51.840 Mhz), T3 (44.736 MHz), and E3 (34.368 MHz) rates in conformance with the
EIA/TIA-612 and EIA/TIA-613 specifications. The actual rate of the interface depends on the
external data service unit (DSU) and the type of service to which it is connected. You can convert
the HSSI interface into a clock master by using the following command in interface configuration
mode:
Command Purpose
encapsulation {atm-dxi | hdlc | frame-relay |
ppp | sdlc-primary | sdlc-secondary | smds |
stun}
Configure HSSI encapsulation.
Step Command Purpose
1 encapsulation atm-dxi Specify the encapsulation method.
2 dxi map protocol address vpi vci
[broadcast]
Map a given VPI and VCI to a DXI frame address.
Command Purpose
hssi internal-clock Convert the HSSI interface into a 51.84-MHz clock
master.