Maybe you're being throttled by your ISP?

No, because the modem was responding slowly to LAN requests - and doing the same tests via the same ISP through the same modem in bridge mode showed full throughput as expected.

In many cases, it only takes a resync to fool the throttling.

The line wasn't resynced when switching between the two modes. And LAN requests were also slowed, which ISP throttling has no control over.

My ISP (BT) supposedly only throttle P2P traffic. There were no signs of any of my tests being throttled.

Like I said, I switched back and forth several times, and got the same results. Various different protocols performed at the same speeds.

Edited by deleted (Wed 02-May-12 19:19:00)

Luckily, I get full speed most of the time.

So do I - just not in router mode.

How much is full speed for you, and what router settings are you using? (And what revision of the modem do you have?)

Edited by deleted (Wed 02-May-12 19:21:49)

As far as I can see, the modem is a router whether it's acting as a bridge or not, as the local interface is ethernet.

It isn't.

The remote (VDSL) interface is also ethernet and in bridge mode it simply acts as a dumb switch, which is much faster than actually handling a PPPoE session, and NAT'ing your packets.

Actually, it uses PTM from the dslam, but you can't send ethernet packets down telephone wires. They have to be encapsulated in frames.

An ethernet cable is in effect no more than two telephone wires so the point is moot.

According to Juniper, "PTM is based on the Ethernet in the First Mile (EFM) IEEE802.3ah standard". It contains a few extensions to 802.3ah but works just the same - i.e. PTM is simply a form of ethernet.

In any case, encapsulation is not a routing function, in bridge mode all the modem does is bridge from one interface to another. It does not perform any functions commonly associated with a consumer or enterprise router. All it does is function as a layer 2 bridge (commonly called a switch).

Finally, ethernet frames *are* frames. There is no such thing as an ethernet packet. Ethernet is the frame within which an IP packet is commonly encapsulated..

And if encapsulating a packet made something into a router, then every ethernet card would also be a router.

Based on what you said above, I'm assuming you don't have your modem in router mode at all.

Edited by deleted (Wed 02-May-12 19:39:51)