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david875

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A Question about Frame Relay

hello,
Recently, i've been configuring a router as a frame relay switch, well everything is ok, since then i had some ideas i was thinking about, does the serial interfaces in the frame relay switch support or can have IP addresses configured in? I can see in many searches that all serial interfaces ports in a frame relay switch are set to "no ip address", ok, now if i have a company that have 3 offices:

1 office in New York, US.
1 office in Paris, France.
1 office in Tokyo, Japan.

How can the ISP in new york link or map the router i have with the frame relay switch of the France ISP and Japan ISP?

My question is: Does serial interfaces in a frame relay switch have ip addresses so the other ISP can map based on these public IP addresses? Or What is the method to make these links between different ISPs using Frame Relay.  Or Frame Relay will not be the best WAN network solution since the offices doesn't exist in the same territory? no?

I'll be happy to hear from you Experts, your experiences in this matter.

Thank you alot.
Avatar of pwindell
pwindell
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Your confusing Switches and Routers.
Frame Relay Routers sit at the edge of the Frame Relay Cloud where it meets the "last mile" links to the LANs paying for the Service.  These operate at Layer3 and have IP#s.  They do "routing", not "switching".
Frame Relay Switches are hidden within the Frame Relay Cloud and and operate at Layer2 and have no IP#s.
They do "switching", not "routing".
 

FrameRelay1.jpg
Avatar of david875
david875

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Hi,

Now you just confused me again, what i know is that frame relay switches are NOT switches !!!! they are routers !!! so there is 1 idea i can tell you if i understood what you just said, there is multi frame relay routers and 1 router act like a root frame relay switch right? so until now you didn't answer me question on how the ISP can link a router to another frame relay cloud exists in another country?? please explain more, are you a CCIE ?
so?
Avatar of Jan Bacher
Frame Relay is layer 2 and is a switch.

Routers connect to frame relay switches.  The router serial interface is configured to encapsulate the packets in frame-relay format (as opposed to HDLC or PPP).

In a typical frame relay environment you have:

1) a router as the frame relay host
2) 1 or more remote routers running as frame relay clients

The frame relay switch maps the PVC (private virtual circuit) of the remote router to the host router.

An ascii example:

                      Router
                          |
           Frame_Relay_Switch
            |             |           |
      router      router     router            


I have had intralata and interlata frame relay host-to-remote connections but not interstate nor inter-country.  Interstate may be available but I would be very surprised if inter-country is available.

You might want to see about independent connections for each location and use a VPN or see if there is a company that can provide an MPLS configuration for all locations.
Not my strongest technology, but I see this has lingered a bit, so will just mention a few things.

A lot of this depends on your Frame Relay network topology.  Due to cost, most of the times, in my experience, Frame Relay WANs were in a STAR (hub and spoke), so strictly a Point-to-Point networking.  Therefore, you connected to the other locations through routing at the central router (site).  

If you had a little more money and could afford a partial or full mesh, then possibly you had connections from each site to every other site in addition to the central office/WAN.

Services like MPLS and eVPN now available from some of the bigger (global) ISPs are probably the better choice these days than Frame Relay; however, you would have to look at costs as I don't have to have my hand in that much anymore as we divested our other global locations.  When we still had them, using our broadband connection, we utilized dedicated VPN connections to the public interface of each site's router versus using Frame Relay.
Sorry, _jesper_, I was typing and didn't see your response.  I would suspect you have way more current working knowledge in this area, so will defer to you on the subject.  My comment will hopefully serve as a "seconding of the MPLS motion" or use of VPN.  

AT&T is the one that provides EVPN if I am not mistaken and so I believe they can provide this because they operate in the European market as well as the US.  I haven't been with the company that implemented that solution for about 6 years, but that in of itself should be hopeful that there is something available that has matured over the last several years as we had no issues connecting our France and other European locations to our WAN and corporate location that was here in the US.  Don't recall a Japan office being in the private mesh, but they could have simply be coming in via VPN as it is sometimes easy to set that up on a single network hardware and then have other clients on the network route through that device to get to the other network.
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mikebernhardt
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david875: Hi,

Now you just confused me again, what i know is that frame relay switches are NOT switches !!!! they are routers !!! so there is 1 idea i can tell you if i understood what you just said, there is multi frame relay routers and 1 router act like a root frame relay switch right? so until now you didn't answer me question on how the ISP can link a router to another frame relay cloud exists in another country?? please explain more, are you a CCIE ?

It is just like I said it is.
It is just like I illustrated
Switches are switches
Routers are router
Just because you can take a device that was originally designed to be a Router and re-configure it to work as a switch is irrelevant,...if it is configured as a switch,...then it becomes a switch.  ISP's do not do this,...Long Distance Carriers do,...and the ISP's simply brokers the connection between the Carrier and you (aka, a middleman)But,...Carriers do not reconfigure regular routers for this,..they use real hardware that was originally designed to be just what they are using it as and each individual device probably cost almost as much $$$ as you would make in a year.,.....just like Mike Bernhardt said in the post just previous to this one.
You cannot configure a router to act as a frame relay switch.  You transport packets from a router across a frame relay network by configuring the router to encapsulate the packets in frame-relay format.
jesper, that's incorrect. You can (and the questioner did) configure a Cisco router to act as a DCE frame relay switch. I've done it myself in order to create a WAN cloud in a lab. You still need additional routers to actually route data across the frame relay switch.
All it's doing is encapsulating the packets in frame-relay format.  Having configured frame-relay switches, there is a distinct difference.

Please don't confuse this any further.  A serial interface on a router configured in frame-relay format is not a "frame-relay switch".
jesper: read http://www.cisco.com/en/US/docs/routers/access/3800/3810/software/command/reference/frcref.html#wp17014

No, the router is not a "frame relay switch." But it acts like one for the purpose of building your own cloud in a lab.

"New York", "Paris" and "Tokyo" are not a lab environment.

I have built several frame-relay networks and I have also configured frame-relay switches.

The author has a real world problem and providing examples relative to lab environments does not provide a solution.

Please don't confuse the author.  A router is not ever a frame relay switch.
I don't think it's a real-world situation, though the author could best answer that for sure. He already said he has configured a router to do frame-relay switching. The cities were referred to in an "if" ("some ideas i was thinking about") question regarding whether he could also put IP addresses on those interfaces and how he would connect offices in those cities together.

So, the answer is:
1. The frame relay switch you created can't be used in a production environment. It's only useful to mock up a frame relay cloud so that you can connect together routers with serial interfaces configured for frame relay encapsulation. To connect real offices together, you need a real frame relay network.

2. The frame relay interfaces on the switch above can't be configured with IP addresses. It only routes frame relay between those interfaces, based on the DLCI maps you create. IP is encapsulated into frame relay by "normal" routers which you connect to your frame relay switch. If you want to do this in a lab, you need additional routers configured with frame relay encapsulation and connect them with an appropriate DTE/DCE cable or rolled CAT-5 to your frame relay switch.

3. A frame relay cloud is owned by a single telco carrier. Frame relay is usually provided over whole or fractional T1/E1 circuits or 56K leased lines. If you're going internationally between countries where more than one carrier must be involved, a carrier will contract a hand-off of the circuit to the other carrier. As mentioned earlier, pure ISPs don't provide circuits. They lease them from other companies which own or lease infrastructure.

We haven't heard from the author in a while. If your question is answered, please award points as you see fit and close it. If not, please ask for clarification.
"How can the ISP in new york link or map the router i have with the frame relay switch of the France ISP and Japan ISP?" does not suggest a lab environment.  Theoretical or otherwise, it's a question that exists outside of a lab.
Either way, the known facts and the answers are the same. This is kind of a dumb argument, don't you think :-)
Thank you for your efforts Experts, well as I can see, you are about to fight guys (just kidding). @jesper : I think that you are confusing me between a router and a switch, I know that frame relay works on the layer 2 which means Data-Link, we all know this right? So What i built is just a lab environment and is not a real situation i faced, anyway I was just wondering if this is the case because i'm someone who have a lot of questions i just want to know how things work in such situation so i can have already an idea and an answer in my mind. I've been looking in the internet about this before i posted this question, I mean what is a frame relay switch, and guess what, it is a Router, is it a special router? I don't know, if it is a switch, is it like a catalyst switch or a cisco 2900 switch? can you jesper explain this? if ISP providers will not use a router like a cisco 2520 or 2522 with 16 serial interfaces to use it for frame-relay so please show me what is this equipement and upload some photos so i can have a clear idea about this special frame-relay switch. There is 2 things, the first is that you never worked with simulation softwares like GNS3 or you already worked on real equipements and start building real Topologies? So if you worked with these softwares like GNS3 what equiment did you use to make a frame relay switch? finally and just 1 last thing, a Frame relay switch is a Router for Sure Only is used for frame relay switching !!! I'm not sure of your knowlegde and your experience because you denied the fact that i can use a router to act as a frame relay switch.

@mikebernhardt: thank you Mike for your answers, you weren't confusing as much as jesper lol so as you said, I made a router to act as frame-relay switch, just 1 thing if you want, if these people who make these emulation software, they should add an equipement for frame relay just in case of confusing the students who study for their CCNA or CCNP for exemple, I know there is a frame relay switch in GNS but it is really poor, you cannot do much only configure DLCIs and this is bad.
I think that you answered my question about linking multiple locations, this is cannot be possible only with the use of other technologies like VPN or MPLS right?
My diagram makes it pretty clear,...Switches inside the cloud (L2),...Routers at the exit points of the cloud (L3).
I never considered it a debate about a "real" FR Switch -vs- a "simulated" one in a Lab,...so I had a bit of a problem with Jesper muddying the waters there.  I even indicated that in a "real life" situation it would be done with expensive specialized equipment designed exactly for such a purpose.  So if I understood your question (and context) properly I think Mike's explaination and my little "artwork" explained it fairly well.
I think that you answered my question about linking multiple locations, this is cannot be possible only with the use of other technologies like VPN or MPLS right?
I don't know what you mean there,...We've been linking multiple locations with this stuff for years long before VPN or MPLS was ever invented.   Yes, FR is Point-to-Point,...but you accomplish it with multple FR Lines, usually in a Hub & Spoke design with the HQ at the Center.  I've been at an NBC Affiliated News Station for 11 years and that is how we used to link all the sister station togethers, dating all the way back to when 56k was consider "fast".
 
The frame relay equipment used by carriers is specialized for the purpose. It may be built into the Lucent or Nortel or Alcatel telecom switches the most of the world's carriers use (Cisco has some carrier-grade equipment too, but it's nothing like what you are used to and doesn't have IOS). Think of the equipment that your telephone connects to and you're closer to it. A photo won't help, it just looks like a box.

As pwindell said, you can certainly use frame relay to connect remote offices. But you have to go through a carrier, who installs a wired circuit to each site from the closest central office and then ties them together through their frame relay cloud. His drawing is pretty on-the-money.
Yea, I fogot to mention something from earlier.  There is no ISP if it is not being used for a "frame relay" to, and for, the Internet.  If it being used as a Private Point-to-Point Connectionbetween two private facilities then you either work dirrectly with the Carrier or with a middleman between you and the Carrier that does the brokering.   The middleman might also be an ISP,..but that would only be a coincidence.
Yeh, I was going to say something about that. The "I" in ISP stands for Internet. A carrier may also be an ISP but they are not the same thing.
Ok, so linking 3 distant offices or sites in different countries will cost alot? I'm talking about frame-relay based on cheap deployment to link these offices, any idea? do you know ISPs who does this?
{sigh}  We just said,...several times,...it is not done by an ISP,...an ISP is the Internet,...this is not the Internet.   It is done by a Long Distance Carrier,...the Carrier may also happen to be an ISP, but that is not relevant.
Cheap deployment?  You're kidding right? The cost of a Frame Relay is based on mileage (distance),....so to span accross countries it would cost $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Why ask us about that?   Call up one of the Carriers and ask them.  Call up an ISP and ask them who you should call,....maybe the ISP you call is willing to broker the connection with the Carrier on your behalf.  Call somebody.
@pwindell: why would i be kidding you ? you see me a kid of 9 years? why wouldn't you answer with explaination without being so nervous i just hate the way you said this damn it i don't need your help
@pwindell: why would i be kidding you ?
When you want a cheap solution Frame Relay is not what people look at.  They look at VPN.
Fram Relay is the expensive robust way to do it that  puts the quality of VPN to shame.  The exact context of my "...you're kidding..." comment was spacifically targeted at your statement of,..."I'm talking about frame-relay based on cheap deployment to link these offices".   It was not meant in any context beyond that.
ok i'm sorry man :)
No problem. sorry if my post came accross wrong.
In the end,...now-a-days,...frame relay is not nearly as popular as it used to be.  VPNs took a huge chunk of that popularity because they can run over a cheap DSL or CableTV internet connection.  But VPN comes no where near the dependability and flexibility of connections based on frame relay.
MPLS is a new-commer that is starting to get popular but it may have distance or geographical limitations.  You'd have to shop around with the Carriers and see what that would be like.  It operates as a Cloud just as the Frame Relay does,...in fact,...to me,...it seem almost like the same thing other than I think it can be multi-point instead of point-to-point