Functionality Provided by the X.25 Services

The X.25 services provide the following functionality:

• Supports X.25 DTE and DCE devices.
• Complies with CCITT/ITU X.25 standards for 1980, 1984, and 1988. Also supports ISO 7776 (layer 2 - LAPB) and ISO 8208 (layer 3). Does not support multilink procedures.
• Complies with ANSI T1.617a Annex G for X.25 Single Protocol Encapsulation Over Frame Relay.
• Transparently forwards X.25 call facilities.
• Supports X.25 SVCs and preconfigured X.25 PVCs.
• Supports local call routing between X.25 ports.
• Requires only one PANL virtual circuit or frame relay DLCI for all X.25 calls between a pair of Passport 4400 units.
• Supports fast select.
• Supports up to 96 X.25 connections (combination of PVCs and SVCs) per Passport 4400 unit.
• Provides unlimited Passport 4400 unit cascading.
• Supports packet sizes containing a maximum payload of 2048 octets. Frame sizes can be up to 2053 octets (LAPB modulo 8) or 2054 octets (LAPB modulo 128).