nanog mailing list archives

Re: Clearwire May Block VoIP Competitors


From: Jared Mauch <jared () puck nether net>
Date: Thu, 31 Mar 2005 10:49:51 -0500


On Wed, Mar 30, 2005 at 08:19:40PM -0700, John Osmon wrote:

On Wed, Mar 30, 2005 at 07:05:44PM -0500, Jared Mauch wrote:
[...]
    I think one of the major problems is that very few people know
how to, or are capable of sending larger g711 frames (at increased
delay, but more data per packet) because they can't set these more granular
settings on their systems.. this means you have a lot higher pps
rates which I think is the problem with the radio gear, it's just not
designed for high pps rates..

So, how are the WISP folk dealing with VOIP traffic as it becomes a
larger piece of their customer's traffic?  Does anyone have a way
to force a given VOIP endpoint to use larger data frames?  Or are

2610(config-dial-peer)#codec g711ulaw ?
  bytes  Specify number of voice data bytes per frame
  <cr>

2610(config-dial-peer)#codec g729r8 bytes ?
  Each codec sample produces 10 bytes of voice payload.
  Valid sizes are:
    10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 
    110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 
    220, 230, 240.

        My Hitachi WIP-5000 also lets me set this locally on the handset
but it uses the delay between packets instead of size..

        The Cisco ata-186 can set this as well:

# -----------------------------------------------------------------------------
#   Parameter:  NumTxFrames
# Access Code:  35
#  Value Type:  Integer  (1 - 6)
#
# Description:  Transmit frames per packet.  
#
#               The frame size for each G.711 and G.729 data packet is 10 ms.
#               The frame size for each G.723 data packet is 30 ms.
#
#    Examples:  To obtain 60 ms of G.723 audio, set the value to 2 (=60/30).
#               To obtain 120 ms of G.723 audio, set the value to 4 (=120/30).
#               To obtain 20 ms of G.711 audio, set the value to 2 (=20/10).
#
#        Note:  Cisco recommends using the default value of 2.

NumTxFrames:2

        

-- 
Jared Mauch  | pgp key available via finger from jared () puck nether net
clue++;      | http://puck.nether.net/~jared/  My statements are only mine.


Current thread: