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Frame Relay Over Tunnel

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kcusscam

Programmer
May 15, 2005
26
US
I know a person who is in a bit if a situation and I think I know the answer but want someone who knows to verify or correct.

They have a 56K dedicated line coming in that needs to go to a offsite location, there is no coper lines going to the remote site, only existing fiber, one pair left. They have a device that uses frame relay at the remote site and need to get it connected through their main site.

I believe than can use two cisco routers with a 56k csu/dsu and pass this frame relay over the fiber by placing on router at each end; one to pick up the 56k frame relay pass it over an ethernet tunnel and use the csu/dsu on the other end to drop the circuit back off and into the remote devices. Does this seem feasible, of course using a coper to fiber media converter or an optical ethernet interface in the routers.

Of course if anyone knows of another or better way to do this please let me know.

Thanks for any feedback.

Jeremy
 
Would it not be cheaper to get an ADSL line to the remote site and the home site and do a site to site VPN?

Burt
 
Actually no I don't think so, ADSL would infer that the telco had any lines to the remote site, the only thing connecting them is a private run of fiber with only one pair open.

Jeremy
 
Just to recap, the device in question only can connect to a 56k frame relay circuit.

Jeremy
 
there is no coper lines going to the remote site, only existing fiber, one pair left.

Does this mean that remote and main are already connected? If not, connect them through the fiber and add the routes to the other routers in the routing table. This must be going way over my head---it can't be this easy...maybe post a topology (ASCII, I don't care), and what is connected to what, what needs to be connected to what, etc.

Burt
 
Yes the remote site and main site are already connected with an IP network that runs over their private fiber. They would like to use there free pair for this circuit. There remote site is out in the middle of no where (I actually mean out in the woods), one dirt road only power and a private fiber run. This circuit will be mission critical and they would like it on free pair.

So what I am thinking they could do, again running a copper circuit is not an option, is the following:

telco_circuit_at_maine_site ==>router 56k CSU/DSU (framerelay) ==> out router ethernet over a gre tunnel ==> in other router gre tunnel ==>out 56k CSU/DSU ==> into propitary 56k frame relay device.

This seems to me like it should work, normally I don't deal with frame relay so I am not 100% sure it will but I am thinking a couple of older 1700's they have kicking around should be able to take care of the issue. I normally deal with frame relay on serial only connections but I believe they can be passed across a gre tunnel and reencoded as a 56k circuit at the other end, that is the real question.

Thanks
Jeremy
 
Just to finish the rest of my thoughts, hit the submit button to quick. I actually think it is really that easy, no advanced routing just a router on each end.

Jeremy
 
Hmmm...still lost. It seems that you are either trying to connect remote to main, which it already is, or have a way for remote to connect to the frame circuit at main, to then be able to connect to all other networks that are in the frame relay mesh. I need a picture...I guess I'm a little slow...
Please explain exactly what you are trying to connect to what, or why you want to pass a frame relay circuit through a tunnel to another location that is already connected to the site in the first place...
Since remote and main are connected via this private fiber, do you mean that you want to get rid of this connection and connect them some other way so that they can use the fiber for something else?

Burt

 
Not trying to connect the remote site to the maine site, it is already connected with a ethernet network. The 56k frame relay circuit comes in with a smart jack at the main site, however the piece of equipment has been moved to the remote site, therefore the smart jack needs to be extended to the remote site over the existing fiber. So in short they need to drag that frame circuit over the fiber and drop it back off as a 56k frame relay.

So just to recap 56k and equipment was at main site, remote site was built without any copper and has an extra pair of fiber. Now 56k is still at main site and the equipment is now at the remote site so the 56k frame needs to be at the remote site so I am trying to determine if the 56k frame can be extended to the remote site through a tunnel.

I would attach a drawing but I am at home without any drawing tools but I can attach one Monday if I am still unclear.

Jeremy
 
I think I see---why not just get a csu/dsu 56K WIC for the remote router, and add routes from remote to main, and vice versa? Why not let remote handle the frame circuit? Either way, it's 56k to the frame relay cloud out to the other side---you're as fast as the slowest link...but remote to main is lightning fast!

Burt
 
The site to site connection does not go through a router, it just just switched on regular old lan switches and the 56k circuit comes from a different provider. I am attaching a drawing. So the question is will this work over a tunnel?

Just incase the picture does not come thorugh (
Jeremy
 
One more fact the remote equipment does not use IP, a proprietary protocol, but I am pretty sure that doesn't matter because they are just trying to extend the actual circuit.

jeremy
 
Why did they move the "frame equipment" to the remote site in the first place? Why not just have the telco (or you) move the smartjack to remote? What is the "frame equipment" at the remote site? What is the frame circuit used for? What protocols does it use if not IP?
What are you planning to use to connect the two frame routers in the first place? Wow...never heard of this one. I think I'll bow out. I am really thinking that there has GOT to be another solution...wow...

Burt
 
Sounds nuts doesn't it. I pose the question on behalf of someone else. Left hand not talking to the right hand i guess. Not sure what the protocol is, I think it is just a data stream stuck on top of frame relay. I just was talking to someone about something and they asked the question. But in truth it shouldn't matter what the layer 3 is just that the layer 2 gets transported. I think the end device is a relay controller of some sort but am not 100 sure. I have been reading the cisco site and you transport frame relay over ipsec so I think it can be done over ethernet, just depends on how the tunnel is setup. I think I am going to lab this with four routers serial to serial-ethernet to ethernet-serial and see how it works using frame relay for the serial connections.

I would have to agree that it should have been planned but as far a datacom wise it really should not be that complicated. As far as other solutions you can buy an off the shelf device that will transport t1's over a fiber connection but I have not been able to find a device that will transport a 56k over fiber. So they only thing I can think of is to digest the 56k transport it over a tunnel and expose the frame as a 56k again.

The part that I don't get is they went to the expense of running fiber but did not run any copper, I guess they didn't need it because they have IP phones. I bet someone when hummm when they went to connect this retarded device.

jeremy
 
Ok, I'm not fully following everything, but got a couple of easy questions to ask.
1. The remote site only has fiber connecting to it, no copper/no smart jack? Why are you wanting to move the equipment that has a copper connections on it to a remote location?

2. I'm assuming this 56k is a private line of some sort that needs to be kept separate from the rest. Is there any reason you can't purchase some equipment other than those copper to fiber transcievers? Personally, I'm not a fan of them, and think you could easily connect remote to main and utilize the 56k by just adding a switch at remote using the free pair of fiber, and put gbic card in your router...depending on it's make/model.

You'd then have something like this:
MAIN:
frame-relay -> smartjack -> router -> fiber
REMOTE:
fiber -> switch

I don't believe you can extend your Smart jack line across fiber like you are talking. I've never tried it, nor have I heard of anyone trying something like that.
 
1. They moved the equipment to where it is because that is where it has to be, facilities had to be changed as I believe they ran out of physical space or something like that.

2. The equipment could be configured to use actual optics instead of transceiver, i know ether way would work if the configuration will work. I believe the configuration using the routers is actually creating a switch.

I did find an interesting article about creating a virtual frame relay switch by placing several serial ports on a couple of different routers and using a gre tunnel to "combine" them into one logical. I believe this sounds exactly like what needs to be done in this case. I do know they have a few 1700 routers so I am thinking they can get a couple of wic-56/64k cards and configure one side to be the dte (smartjack side) and the other side as a dce which would allow the equipment (the stuff moved) to interface with the router on the remote end. From there you should be able to configure the two routers and a frame-relay switch and configure the encapsulation type on the serial interfaces to be frame relay.

All the other solutions that I could find are well over 15,000, including the option of doing a coper run, even if they had to buy new routers i should be well under 5000. I think a real frad would probably be the best if they had more than a 1 circuit requirement.

I believe the last question I have is can the wic-56/64k cards be configured as the dce, I have never used this card but I believe it is configured like any other serial card?

Thanks for the input and suggestions thus far.

Jeremy
 
I can understand the layer 2 not having to be concerned with layer 3 protocols, but I was asking to maybe offer a less complicated (and seemingly more obvious) solution, such as what lerdalt has suggested. Just wondering if access lists could be created and separation via vlans, since ethernet switches are already connected.
As far as the tunnel carrying the frame relay---that is backwards...the tunnel (IPSEC, GRE, whatever) can go over frame relay. Something has to exist before you can transport it, like layer 1 (copper/fiber) layer 2 (frame relay), layer 3 (your GRE tunnels, or L4 fashion)...so, it sounds like you are wanting to carry frame through a tunnel without an existing layer 2 to begin with!
Also, what do you mean running out of room??? The smartjack is a LOT smaller than a new router! This thread is definitely interesting...I'll give you that!
It could be that I am just totally lost...

Burt
 
Actually there is a layer 2, ethernet or using ipsec it will go over ip, kind of like a VPN. Actually it appears that when you pass data over a gre tunnel like this it appears or behaves like MPLS but without the MPLS.

Think of it kind of like openvpn or any ipsec/ssl vpn for example the ip traffic is carred over an existing layer 3. The layer 2 data for the frame is the data payload of ethernet or ip depending the encoding.

In this case layer 1 will be the fiber, or I could use an existing VLAN as the transport for the gre tunnel, layer 2 will be be ethernet, layer ip with ip carrying the gre and the gre payload containing the layer 2 frame relay.

jeremy

 
But you're connecting the two sites TWICE with 2 different connections! Just use the existing ethernet to pass frame relay traffic back and forth! Just a routing/vlan issue! Nothing extra is needed---traffic comes into main site via frame relay, separate from any other traffic, and is passed over the fiber, but nobody sees it other than the frame router at the remote site because acls are in place.

This cannot happen because they decided to move the frame equipment from the main site to the remote site because they ran out of room, but left the smart jack at the main site. Whoops. They might need that for something...
So now, this person on whose behalf you are posting all of this, is wanting to somehow pass the frame encapsulated traffic that comes into the smart jack over the fiber to the other site and into the "frame equipment" so that it can do its funky thang...is this about right?
So now---what exact equipment is connecting the fiber from the main site to the remote site? Do these devices have ethernet ports on them?

Is there any reason to NOT move the smart jack to the remote site? Whomever is asking you to post this...do me a favor---have them maybe ask the question...I am sure you thought of this, and said person maybe doesn't want to because...

ah, better not...lol

Burt
 
Actually my first question was want to you mean there is not copper, what where your plans. Pretty much the reply was didn't think we would need any copper. They thought they could use ethernet media converters to pass the frame circuit to the other side of the fiber. Regardless if the gre tunnel passes over the existing vlan or just another pair of fiber doesn't make much of a difference in regards to making it work. Right now they are monitoring the equipment from the remote site, when the link is up they can monitor it from the main site. They will want it on the other pair of fiber so the link doesn't or cant get congested, I know you could do some qos but do you really think they can manage that if they forgot the smart-jack? My first response was "run some copper", there response most likely not going to happen. My second response put some kind of light span in, there response to much money. My next statement, let me see what I can come up with, here we are. The reality is they probably have more than one free pair of fiber but they did put in a pair for this.

This is a pain in the but project but the reality it is making a good exercise.

Jeremy
 
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