×

Warning message

  • Cisco Support Forums is in Read Only mode while the site is being migrated.
  • Cisco Support Forums is in Read Only mode while the site is being migrated.

VSAT and Voice

Unanswered Question
Jul 7th, 2006
User Badges:

We have a customer with CM 4.1 at their main site and moving trailer truck with CME 4.0 running on a 2801 router. They are using 7940 and 7920 phones in the trailer.


When the trailer is parked at main site it works fine we can make calls between CME and CM phones.


Here is my challenge in the Trailer they have Satellite connection to Internet (Please note just to Internet not Point to point) While the trailer is on the road they want to setup a VPN tunnel to their main site and make calls between Trailer and Main site.


My another Challenge is Delay on SAT is somewhere from 600 - 1100 msec's.


I know with this delay we cannot do voice but we are still trying to satisfy the customer so is there anyway we can accomplish this with "Playout delay cmd" OR using RBSCP OR NM-VSAT module or any 3rd party solution ??!!


FYI..Currently it is an ethernet hand off from Satellite which is connected directly in to 2801 router.


Any help will be really appreciated.


Balu





  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 3 (2 ratings)
Loading.
chris_harris@el... Fri, 07/07/2006 - 13:43
User Badges:

You just need a fixed delay through the VSAT - if it is a consistent 1 sec, then calls would be fine - the jitter is what will kill the call not the delay.I haven't seen any devices that will allow the jitter buffer size grow, or be set, to 500msec. Is the carriers Internet connection responsible for the jitter? The VSAT should be a fixed delay ~400msec -

chris_harris@el... Fri, 07/07/2006 - 13:46
User Badges:

You just need a fixed delay through the VSAT - if it is a consistent 1 sec, then calls would be fine - the jitter is what will kill the call not the delay.I haven't seen any devices that will allow the jitter buffer size grow, or be set, to 500msec. Is the carriers Internet connection responsible for the jitter? The VSAT should be a fixed delay ~400msec -

balukr Sat, 07/08/2006 - 05:59
User Badges:

Chris,


How would you check the Jitter ? Is there anyway you can check on the router.


I'll check with customer for who is responsible for jitter.


Again Thanks for all your help.


chris_harris@el... Mon, 07/10/2006 - 06:59
User Badges:

From the router, ping the remote end-user router and record the replies (use an extended ping to set the number of attempts to 1000) and copy them to an excel spreadsheet - then go through the replies and measeure the inter arrival times between each packet. This is the easiest way.


For an automated process, there are several tools available. One of the best tools is setting up RTR on the routers and measure with IP SLA/WPU WAN Performance Utility (Cisco); this will allow you to see one-way delay/jitter.

Actions

This Discussion