On 8/22/07, maillistnoll <[EMAIL PROTECTED]> wrote: > I've taken a quick look through the supported protocols and what's in CVS, > but I can't seem to find any decode for DS1 (T1) signals. > > Before I go writing one, has anyone tackled this decode before?
DS1 is usually handled by hardware, the line-code is electric impulses (HDB3, AMI) so it's hardware that deals with it, finding DS1 frames out from a bitstream could be done by software, but if you have an interface that handles HDB3 or AMI it probably does handle sync and multi-frame alignment as well. And it probably handles also "higher levels" of framing as well (like FR, HDLC, MTP2, ATM, etc) so libpcap (that's what wireshark uses for capture) gets fed with frames already extracted from the bitstream by the hardware and its driver. Considering that Wireshark handles frames (not electric signals or bitstreams) and most hardware that can allow to connect a computer to an E1 will do the framing by itself. There's little use for such an implementation, There are a lot of interesting bit oriented protocols out there whose implementation makes little useful sense in Wireshark even if in some cases they can actually be found encapsulated in packets of other protocols (e.g. bitstreams of V.110 or PCM encoded V.32->V.90 might be found in NbUP frames). The DS1 case is more extreme the only cases of frames that can contain DS1 bitstreams I can think of are SDH and DS3 for which the same issues regarding hardware apply. Luis -- This information is top security. When you have read it, destroy yourself. -- Marshall McLuhan _______________________________________________ Wireshark-dev mailing list [email protected] http://www.wireshark.org/mailman/listinfo/wireshark-dev
