Configuring the AAL and Encapsulation Type

Cisco,çom

R7(config-if-atm-vc)# encapsulation ?

aal5ciscoppp Cisco PPP over AAL5 Encapsulation aal5mux AAL5+MUX Encapsulatic aal5nlpid AAL5+NLPID Encapsulation aal5snap AAL5+LLC/SNAP Encapsulation

Cisco,çom

R7(config-if-atm-vc)# encapsulation ?

aal5ciscoppp Cisco PPP over AAL5 Encapsulation aal5mux AAL5+MUX Encapsulatic aal5nlpid AAL5+NLPID Encapsulation aal5snap AAL5+LLC/SNAP Encapsulation

© 2002, Cisco Systems, Inc. All rights reservec

Disco CCIE

4-56

Use the aal5mux encapsulation option to dedicate the specified virtual circuit to a single protocol; use the aal5snap encapsulation option to multiplex two or more protocols over the same virtual circuit. Whether you select aal5mux or aal5snap encapsulation might depend on practical considerations, such as the type of network and the pricing offered by the network. If the network pricing depends on the number of virtual circuits, aal5snap might be the appropriate choice. If pricing depends on the number of bytes transmitted, aal5mux might be the appropriate choice, because it has slightly less overhead.

Configure the ATM adaptation layer (AAL) and encapsulation type with the command beginning in interface-ATM-VC configuration mode:

encapsulation aal5encap

The options for encap are: R7(config-if-atm-vc)# encapsulation ?

■ aal5ciscoppp: Cisco Point-to-Point Protocol (PPP) over AAL5 Encapsulation

■ aal5mux: AAL5+Multiplex (MUX) Encapsulation

■ aal5nlpid: AL5+ Network Layer Protocol ID (NLPID) Encapsulation

■ aalSsnap: AAL5+Logical Link Control/Subnetwork Access Protocol (LLC/SNAP) Encapsulation

■ ciscoppp: For Cisco Point-to-Point Protocol (PPP) over ATM. Supported on ATM PVCs only.

■ nlpid: Allows ATM interfaces to interoperate with High-Speed Serial Interfaces (HSSIs) that are using an ATM data service unit (ADSU) and running ATM-Data Exchange Interface (DXI). Supported on ATM PVCs only.

■ snap: The only encapsulation supported for Inverse ARP. Logical Link Control/Subnetwork Access Protocol (LLC/SNAP) precedes the protocol datagram.

When mux is specified, a protocol is required: R7(config-if-atm-vc)# encapsulation aal5mux ?

■ apollo: Apollo Domain

■ appletalk: AppleTalk

■ ipx: Novell Internetwork Packet Exchange (IPX)

■ ppp: VC MUX PPP over AAL5 Encapsulation

■ vines: Banyan Virtual Integrated Network Service (VINES)

■ xns: Xerox Network Services

Was this article helpful?

+1 0

Post a comment