[Asterisk-Users] Is Gigabit Ethernet necessary?

[Kevin P. Fleming]

steve at daviesfam.org wrote:

> At worst a packet would have to wait 19 packet times. Which is 300
> microseconds for 200-byte packets at 100 megabit/sec.

No, no, no... Steve, don't you see? He's using those magical switches 
that do TDM on Ethernet; they sense how many nodes you have plugged in 
to each port on the switch, which other nodes they are communicating 
with, and then they divide up the bandwidth mathematically :-) That way, 
you _always_ get 5Mb for your use if you are one of 20 users, and noone 
else can use it if you don't!

(yes, tongue firmly planted in cheek)

You could use a _10Mb_ full-duplex switch and run 20 VOIP phones without 
any trouble at all; even using G.711 u-law, each call path only requires 
around 100Kb/s, so you'd still only be using 20% of the bandwidth 
available on the single port leading to the server. If the VOIP phones 
are allowed to send media directly to each other, the picture looks even 
better.

I still think using a GigE card in the server is a good idea, but mostly 
for the other reasons mentioned already. The single-packet latency will 
be lower (because the transmission time from packet-start to packet-end 
will be lower), and the interrupt load on the server will likely be 
lower because the NIC and the driver will be more intelligent.