1760-V as a PSTN switch?

mikeeo

I've looked at the old docs for the 1760-V and it looks like I can stick (1) VWIC-2MFT-E1/T1 (1) VWIC-1MFT-T1 and a VIC-2FXS without issue.

Anyone have a configuration like this or similar?

Thanks

cas27

Mikej did something just like that and Im about to setup something very similar.

He talks about it in this thread. http://www.techexams.net/forums/viewtopic.php?t=37851

mikej412

cas27 wrote:

He talks about it in this thread. http://www.techexams.net/forums/viewtopic.php?t=37851

mikej412 wrote:

I also have a 1760-V with a VWIC-2MFT-T1 in the POTS Cloud that I can swap in here instead.

It does have 2 VWIC-2MFT-T1s, a VIC-2FXS, and a VIC-2DID

1 FastEthernet interface
4 Channelized T1/PRI ports
1 Virtual Private Network (VPN) Module
2 Voice FXS interfaces
2 Voice DID interfaces

The MC3810s have been working fine so far, so I haven't installed the 1760 as a permanent member of the POTS/PSTN cloud yet

mikeeo

Mike from the docs on the 1760 it looks like you can fill all 4 slots with VWIC's but only the first two with WICs? am I reading that correctly? all 4 slots can be voice enabled?

mikej412

The doc makes it sound like you could install 4 analog VICs, not 4 VWICs -- but I've never tried VICs in the 2 left slots. The router chassis does say that only Voice Interface Cards are supported in the 2 right slots.

I've only been able to install 3 VWIC-2MFT-T1s

1 FastEthernet interface
6 Channelized T1/PRI ports
1 Virtual Private Network (VPN) Module
2 Voice FXO interfaces

I never could get the 4th VWIC to go in the far right VIC slot on 2 1760s that I tried (and I didn't want to force it). I was waiting until I did a memory upgrade and had a 1760 open to see why it wouldn't fit in that slot.

nagen

But I have read some where in cisco docs you cannot configure more than two PRI_T1 groups,
only two vwic ports can be configured as PRI; even if you have more than two ports and enough dsp resources, 1760 only allows you to configure PRI on two ports but you can configure CAS on all available ports if you have enough dsp resources.

mikeeo

nagen wrote:

But I have read some where in cisco docs you cannot configure more than two PRI_T1 groups,
only two vwic ports can be configured as PRI; even if you have more than two ports and enough dsp resources, 1760 only allows you to configure PRI on two ports but you can configure CAS on all available ports if you have enough dsp resources.

Can anyone confirm you can only create (2) PRI-GROUPS?

mikeeo

I think I just found my answer.

http://www.cisco.com/en/US/docs/routers/access/1700/software/feature/guide/t1e11700.html#wp69360

I need to be able to terminate 3 T1 PRI's and 1 E1 PRI. If I use a VWIC-2MFT-T1 and VWIC-2MFT-T1/E1 that should do the trick.

Mike can you verify you can create 2 PRI-GROUPs per slot?

That should be in-line with the voice lab's PSTN switch.

mikej412

The 1760 data sheet says it supports a maximum 30 digital DSD channels through T1/E1 VWICs.

This FAQ Link to Cisco Digital 1-port and 2-port T1 Multi-Flex Voice WICs says:

Cisco 1721/1751/1760 Chassis WIC Slot

The Multi-Flex Trunk can only be installed in the chassis slot0 and slot1 WIC slots. Each T1 can be configured with a channel group to generate a virtual serial interface in the running configuration. At most, you can have two channel groups per VWIC. This means that a 1-port VWIC T1 controller can be configured with (at most) two channel-groups, and a 2-port VWIC can be configured with (at most) two channel-groups on one T1 controller or one channel-group per T1 controller.

If the Cisco 1751/1760 has voice DSPs installed, the Multi-Flex Trunk can be configured as a PRI or CAS voice Telephony interface. A 1-port T1 VWIC can support a single full PRI or a fractional PRI and a channel-group. A 2-port T1 VWIC can support up to two PRIs or one PRI and one channel-group.

I'll see what I can do with that 3rd VWIC it recognized in slot 2 when I get a chance.

nagen

you are trying to emulate PSTN so its going to be network side, meaning clock source is internal, 1760 router cannot provide internal clock to 4 vwic ports. I made a lab set up of 1760 with 2 vwics-2mft-di and I configured first vwic as network side to get internal clock.

tdm clock T1 0/0 both import onboard internal
tdm clock T1 0/1 both import onboard internal
but I when I try to apply same commands to my second vwic it give an error message like this one
Router(config)#tdm clock t1 1/0 both import onboard internal
% T1 data switch not available for this configuration
Router(config)#
it seems like you can configure internal clock source only on two ports.

Now i am reading this doc I will see how it works ....

Clock Configuration for Cisco 1751/60 Routers

I have seen a PSTN set up on a 2811 it works great this router is full of resources awesome.

mikeeo

Looks like you can install (2) two-port E1/T1's in slot 0 and 1 but not exceed 30 PRI channels. Which is fine for the lab.

mikeeo

nagen wrote:

you are trying to emulate PSTN so its going to be network side, meaning clock source is internal, 1760 router cannot provide internal clock to 4 vwic ports. I made a lab set up of 1760 with 2 vwics-2mft-di and I configured first vwic as network side to get internal clock.

tdm clock T1 0/0 both import onboard internal
tdm clock T1 0/1 both import onboard internal
but I when I try to apply same commands to my second vwic it give an error message like this one
Router(config)#tdm clock t1 1/0 both import onboard internal
% T1 data switch not available for this configuration
Router(config)#
it seems like you can configure internal clock source only on two ports.

Now i am reading this doc I will see how it works ....

Clock Configuration for Cisco 1751/60 Routers

I have seen a PSTN set up on a 2811 it works great this router is full of resources awesome.

I'm running into the same issues, but the docs say you can run 4 vwic ports.