ATM via serial interface

[jjeffcoat]

Can I terminate ATM into serial interface without a front-end device to perform SAR function?

[gmarogi]

My guess is you will need a ADSU if you want to connect the serial interface to the ATM network. If it is a normal point-to-point link, you can then connect them without the ADSU and still use ATM-DXI encapsulation on the serial interfaces. This doc talks about running ATM on serial interface :

http://www.cisco.com/en/US/products/sw/iosswrel/ps1826/products_configuration_guide_chapter09186a0080087f83.html

[beng]

Hi,

You have to use ADSU because of the following:

1.The router's serial interface prepends a variable-length frame with a DXI

frame header and (optionally) an Logical Link Control(LLC)/Subnetwork

Access Protocol (SNAP) or network layer protocol identification (NLPID)

header, and creates a DXI frame.

2.The serial interface transmits the DXI frame out to the ADSU.

3.The ADSU removes the DXI header and retains any LLC/SNAP or

NLPID header.

4.The ADSU performs the ATM-level processing by appending an ATM

adaptation layer 5 (AAL5) trailer and then segments the packet into ATM

cells.

5.The ADSU analyzes the DXI frame address (DFA) and maps the VPI/VCI

contained in the DFA to the virtual path identifier or virtual channel

identifier (VPI/VCI) fields in a standard ATM 5-byte cell header.

6.The cells are transmitted onto the ATM network.