nanog mailing list archives
Re: Cable networks RE: best effort has economic problems, maybe OT
From: Petri Helenius <pete () he iki fi>
Date: Sun, 30 May 2004 21:19:33 +0300
Christopher J. Wolff wrote:
The bandwidth you quote refers to the unencoded signal bandwidth. The actual transmission has the same channel spacing than traditional television, be that NTSC or PAL or SECAM. Terrestial applications typically carry 20-25 megabits and cable & satellite applications typically 40-50 megabits per channel/transponder. HDTV channel usually consumes 19.8Mbps for video plus some extra for audio + multiplexing information. So a channel that used to carry one NTSC analog channel over the air can be used to carry one HDTV channel or in the case of cable/satellite networks, two.Folks, This is a great discussion. I'm interested in understanding these types of limitations in the context of HFC cable networks. In my opinion, HDTV channel bandwidth (30mhz?) , increased demand for voip, and growing demand for IP connectivity is going to stress the cable network model as well, forcing cable operators to convert everything to IP before going out across the wire. Any input is appreciated.
I´m all for encapsulating all transmission to IP packets, because it would make a lot of things easier, but I would suspect some places need to freeze first :-)
Pete
Current thread:
- Re: best effort has economic problems Gordon Cook (May 29)
- Re: best effort has economic problems Mikael Abrahamsson (May 29)
- Re: best effort has economic problems Eric Kuhnke (May 29)
- Re: best effort has economic problems Mikael Abrahamsson (May 29)
- Cable networks RE: best effort has economic problems, maybe OT Christopher J. Wolff (May 30)
- Re: Cable networks RE: best effort has economic problems, maybe OT Petri Helenius (May 30)
- Re: Cable networks RE: best effort has economic problems, maybe OT Stephen Sprunk (May 30)
- Re: best effort has economic problems Eric Kuhnke (May 29)
- Re: best effort has economic problems Mikael Abrahamsson (May 29)
- Re: best effort has economic problems Simon Leinen (May 31)
- Re: best effort has economic problems Mikael Abrahamsson (May 31)
- Re: best effort has economic problems Vicky Rode (May 29)
- Re: best effort has economic problems Mikael Abrahamsson (May 30)
- RE: best effort has economic problems Neil J. McRae (May 31)
- Re: best effort has economic problems Laurence F. Sheldon, Jr. (May 31)
- <Possible follow-ups>
- Re: best effort has economic problems joe mcguckin (May 30)