STUN SDLC Connection to AS/400

[joe_chris]

Hi,

Current Environment:

The customer has terminal at remote branch that connects via SDLC link to AS/400 host at HQ. The current connection is 90's style TDM leased line with synchronous modem at both ends.

Requirement:

The customer would like to migrate to modern packet based WAN using Metro Ethernet.

Question:

1. Can I use STUN in this case?

2. Is it possible to setup multiple STUN tunnels on a pair of router?

3. What type of smart serial cable is compatible with the ISR WIC connection in this case? Any modification require for standard smart serial to DB25 cable?

A million thanks in advanced.

Sent from Cisco Technical Support iPhone App

[mwinnett]

Sure, stun will work fine in this case. There are number of different options

1: stun basic - encaps everything from the sdlc into tcp, tunnel from router A to router B, decaps back into sdlc on the remote

2: stun sdlc - match on the configured sdlc address and send to remote router, this allows for more complex scenarios (send sdlc addr c1 to remote B and sdlc address c2 to remote C etc).

3: stun sdlc local-ack - as per #2 but also locally-acknowledge control frames and only send data over the wan

You only have one tcp connection between a pair of stun rouiters, but you can tunnle multiple sdlc connections. These are identified by sdlc address and stun group. eg: config for one peer

stun peer-name 10.48.64.26
stun protocol-group 2 sdlc
!
interface Ethernet1/0
ip address 10.48.64.26 255.255.255.0
!
interface Serial3/0
mtu 2104
no ip address
encapsulation stun
serial restart-delay 0
clockrate 64000
stun group 2
stun route address 11 tcp 10.48.64.18

Cisco have DCE (clock)  & DTE (clocked) cables for x21, v35 and v24 (I think this is db25). If you want the router to clock the connection then take a dce cable and configure clockrate on the interface, otherwise use dte.

Stun is well established but I suspect is not widely deployed on newer platforms (29/3900s). There might be issues with some of the newer WIC card simply due to lack of exposure.

Matthew