question about "routers" and PPP

I`ve noticed that for user,pass PPP(whether in the router or in windows) seems to use a username with an @ like

is that always the case? anybody know why?

I am in the UK, the ones I Have seen have all been PPPoA. Is it only PPPoA that have that?

With some USB modems the PPP is done in windows. Is that still PPPoA ? (I am guessing so, since isn`t A for ATM , which is to do with the service provider)

Yet This link here

formatting link
a windows screen that suggests that USB modems use PPPoE, and that the username does not have an @. (windows screen obtained by ctrl network connection wiz..connect to internet...manually) I can guess that they use PPPoA in UK, and PPPoE in america.

Is it also the case that PPPoA tends to use an @, and PPPoE tends not to ?

Is there a name for a device whose function is PPP? I am guessing not. I guess it is another function they bundle into the device called a "home router". I know with dial up modems it is always windows that does it. And I have heard that a router can be put in bridge mode and then PPP can be done in windows. Is that right?


Reply to
Loading thread data ...

No, it can be anything.

Why not?

Two things. Realms and that usernames for many services look like email addresses anyway.

No, anything that authenticates can have any username they wish.

It could be.

Technically the A in PPPoA is for AAL5, which is one layer ontop of ATM. Alot of people commonly put that back as ATM.

Yes, there could be USB modems that require PPP authentication (ie. Intel 3200 is one discontinued one. Not too familure with the batch out there). Or, they could be simple bridges, and depend on Windows built-in PPPoE to handle those functions.

Either way, the username can be anything the service provider wants to run.

I run almost all PPPoA in the US, as do most ISPs using Qwest as a facilities provider.

No. There's no correlation.

eh? Lost me alot on this one.

Alot of what you are asking depends alot on the service provider, and what they can provide you. You're trying to generalize too far.

Reply to
Doug McIntyre

if an ISP uses PPPoA e.g. if using a "Router" one selects PPPoA and it connects. Then, if one was to change the router for a USB bridge, and connect via windows.

Would the built in windows thing be PPPoA or PPPoE?

PPP is something from the DSL world. A plain router would just do routing and not know about PPP. Router is really a function. The boxes people have at home act as a router, bridge, modem, dhcp server. So, since you know the DSL world.. I ask, is there a name for a device that does PPP?

Reply to

Bridge is such a generic term. Is it really a bridge? Or is it a modem? There are both types of boxes out there. Both terms are abused so often as to what they actually are. Maybe thats part of some issue, when people commonly call anything that terminates the signal a router/bridge/modem depending on what they are used to, not depending on what it actually is, it tends to get a bit confusing.. (ie. a router will make layer-3 routing decisions across two or more interfaces. a bridge will pass layer-2 packets between two interfaces. A modem generally has one interface and some method to put the data back out somehow, serial, usb, whatever). A router or bridge would "contain" a modem as part of its hardware, although you won't see it.

I'm going to assume that everything is ATM here for the most part. Some ISP networks are built on pure IP now-a-days, although the classic DSL since the ANSI/ITU standards came along was built on ATM.

A DSL USB bridge would imply that it takes the DSL signal in, reassembles the ATM cells into regular Ethernet frames. Then on the USB interface, it would present an Ethernet NIC interface to the OS. The OS then if using PPP, implement the PPPoE stack on the Ethernet interface that pops up, do the phases of PPP and get online. A Zoom 5615 is this sort of device.

a DSL USB modem would imply that it takes the DSL signal in, and presents a modem interface to the OS over the USB interface. Typically an ISP running this sort of configuration could be talking PPPoA or PPPoE to the far end, because there's no Ethernet involved, virtual or otherwise. You can not talk PPPoA over ethernet (ie. like the DSL Bridge I discussed above), it *has* to be over some sort of ATM interface, which the DSL USB modem can provide. In this setup, you get a modem showing up on your OS, you dial using it with normal Dialup Networking, usually dialing the ATM VPI/VCI to talk with as the phone number and plugging in your ISP username and password in the normal fields. A Zoom 5510 or Intel 3200 is this type of device.

PPP is from long long before DSL was around, we should be coming up on

20 years pretty soon. I was doing PPP over analog modems in 1993. Such an easier solution than SL\\IP. PPP is also used in many other applications. Many T1s run PPP as their layer-2 protocol. I've seen it used over X.25 networks. Appletalk and IPX protocols can run over it. PPP was an existing solution adapted by DSL to provide the same benefits. The design of PPP was obviously well done to provide such extendibility for so long.

A plain router has had PPP in it for some time. cisco IOS introduced it in 10.0 IIRC, somewhere around 1994. A router in classic sense just is a device that can make layer-3 protocol decisions between two or more interfaces.

Most DSL routers have had PPP stacks built into them. There have been a few (lower-end than normal Speedstream comes to mind) that have not, even though PPP usage in the DSL world was long established. A few years ago, customers coming to me with weird random devices asking about compatibility, I'd have to read the tech specs carefully to see if they did support PPPoA or not. Sometimes they did, sometimes not.

There is not a designation of a network device that says it can talk PPP, although most (if not all currently shipping ones) DSL routers can do so. PPP is just one of many 100's if not 1000's of features/protocols a router has to deal with.

Any non-DSL network router would have the PPP protocol in it from before the time that DSL existed. (ie. cisco, juniper, etc).

So, no there is nothing that says a box can do PPP other than its tech specs.

Reply to
Doug McIntyre Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.