Metro Ethernet Services – A Technical Overview Ralph Santitoro Introduction This white paper provides a comprehensive technical overview of Ethernet services, based on the work (as of April 2003) of the Metro Ethernet Forum (MEF) Technical Committee. The paper is intended to help buyers and users of Ethernet services understand the. Property Description; running (yes no): Whether interface is running. Note that some interface does not have running check and they are always reported as 'running'.
Hi all,I have a quick question. Is it possible to run L2L IPSEC VPN via a Metro-E connection? It doesn't make sense to do something like that via Metro-E but this connection is with a partner therefore on both ends, firewalls are in place.
WIth port forwading, NATting, etc,etc, I ran into problems to provide additional services because of that. I am hoping a L2L IPSEC VPN on both ends will solve this problem once and for all. The only question is to be sure in fact a Metro-E is just a ethernet connection and really no difference from setting up a L2L IPSEC VPN via the internet.Thank you for your help.
I have to do a presentation at the end of this week. I have read EVERYTHING online, and I understand the concepts of E-Tree, E-Line, E-LAN (?), and the MEF 2 Protection standards. However, I don't understand what the main idea is.Why not just use Frame Relay? Does carrier ethernet use routers, or is it only for switches? If it's switches, where does the data go from my computer, and what happens if I need to access Google? Does the CE provider forward it out for me? Is the goal of CE just to transfer any kind of signal into an ethernet signal (cell phones, DS lines, ISDN, optical)?If anyone can help explain to me why CE is so good, and how it is used, it would be a huge help.
Thanks for any help in advance. Carrier Ethernet is the next step in delivering services between point a and point b.
Lets say you have 2 offices in the same city. You need network connectivity between them, and its the year 2000, so you get a point to point T1 between them and buy routers to go on each end. You are a successful business and you need more speed between the sites, so you add a second T1. But, when you bought your first routers you were scraping by, so you only bought the cheapest routers you could get by with (Cisco 1601s for example). Now you have to upgrade to larger routers to support the 2 T1s, but now you are a smart business man or woman and see the point in modularity so you go with something like a Cisco 2611 and multilink the 2 T1s together.This has you going well until you, being ultra successful in your city, buys out the competition and the 2 offices they had. Now you must connect those sites to your existing network, and it is time to upgrade routers again so you have the spots to plug all the remote offices in.
Your first office you decide will be your core, cause thats where you work, so you put in a bigger router, a Cisco 3662 maybe (because you grew in a short amount of time and it's still the early 2000s). So now you have your core office, with 2 T1s each to your other branches, requiring 6 interfaces on the 3662 and a router with 2 interfaces at each of your remotes. You move your first 2611 from the core to a site, and buy another.You keep this setup for a year and are ok with it, then you add another remote site. No problem, and another T1 interface to your 3662 and another 2611, and keep going. The down side to this setup is T1 interfaces are expensive and somewhat specialized.
Now that you have 8 T1s coming into your 3662, you start to wonder, hmmm, is this the best way to do this, keep adding 1 card every time. So you call up your carrier and say hey sales guy, I was at the bar the other night and this guy told me I should get a DS3 for my T1s and I might save some money. He says sure, no problem, let me get one ordered for you and mentions something about you needing a Channelized DS3 card to support the T1s on it, and you say no problem, (you did spend the night at the bar and are a bit hungover so your not sure what that meant or why it matters). But you keep thinking about it and wondering, is growing my sites at 1.5 meg T1 increments the best way?
I mean, if you need 10meg to a site, your looking at 7 T1s. You also do a bit of research and find out there is no channelized ds3 card for your trusty Cisco 3662 router so again, its time to forklift replace it (although a 3662 is a bit small to bring a forklift in).
So you call sales back and say hold up! Do you have any other offerings for me and explain you need 10 meg to one site, dont want to replace your router as its 2008 and the economic downturn just hit, etc.So then he tells you, how would you like to try our newest service, Carrier Ethernet (or Metro E)?
He goes on to explain it is nice because you no longer have to buy those special T1 or T3 interface cards, you just use vacant ethernet ports to connect with. Additionally, they offer speeds of 3, 5, 10, 20, 35, 50, 75 and 100 meg. This greatly simplifies your network in many ways.I hope this story helps a bit, if nothing else, I enjoyed writing it.
Metro E is great because it makes it easier to interface with equipment, and better speeds are offered. In the old days, if you had to have a 100meg connection, you were looking at an OC3 interface which was thousands and thousands of dollars. Everything has an ethernet port, making life easier.To your questions:Frame relay and ATM are dieing monsters.There are different ethernet offerings depending on the carrier. If its in a local region, you often just get a port on their equipment which does Q-in-Q to ship your traffic off to the far end and you never see the provider equipment in the middle at Layer 3.
Some carriers implement it over a larger area, requiring Layer3 VPN setups where you may see some of their routers in the middle.Many carriers are now offering fiber optic to home services using ethernet as the delivery and hand off to the home user. In this scenario, yea, they just hand you a port and carry it Layer 2 to their routers and ship out your packets.Hope this way to long example helps you some.
Frame Relay was heavily used back in the day because of its multi-point capabilities and another point they don't talk about in books - cost. As a regional ISP, we used frame relay to establish connections to remote cities and hung our dial up modem banks off of the routers. We could have done this with point to point t1s to each city back to our core, but T1s like that are usually mileage priced. Frame relay was usually a flat rate as long as you put it anywhere in the LATA.
With technology changes and more competitive pricing, prices have been reduced significantally on many services, rendering FR less attractive. The last time I touched FR outside of lab was.2005 or so when I rebuilt some customer WANs with point to point T1s.Related to that, ISDN BRI was often used for the most remote of locations where bandwidth was very expensive to get to and is mostly gone now thanks to wide spread cable modem/DSL and VPNs. ISDN PRI is still relevant for phone connections in many areas, but is starting to be phased out for SIP trunks. You are not at a loss to have learned about those technologies, however.
In your career, you will run into all sorts of weird stuff. Glad I helped you understand it a bit.
I work in a data center where we host services for our clients. We still have clients coming in on t1s (l(a lot of mpls over t1, some strict t1s depending on customer needs, the majority of which comes I'm on ds3). We have started to get some metro, most carriers still can do cross state with it though. Its pretty awesome though because its a layer 2 hand off which means we can just run eigrp like with straight t1s and don't have to deal with the complexities of redistribution of bgp into the eigrp process and the fun it creates with multiple branches each with their own fail overs. The only thing he left out is the actual technical answer to 'What is Carrier Ethernet'The answer is:. I have several imlemented and essentially the service provider will bring in fiber to a switch they own that's in your facility (We got Cisco 3570 series) they give you a Gigabit copper or Fiber port off of it to connect to your LAN.
You pay for how much you want to use in various tiers. It is essentially a Layer 2 connection to your other office which will have the same setup. I suggest though that most people route over the link to limit the traffic that is going over it, and that is what we do.
We did it with layer 3 routing images on switches and VLAN routing. You can order internet service over Ethernet in which case there would be no MPLS involved. Like I said in my big schpiel earlier it is quite commonly used as a transport to an MPLS backend but not necessarily so.I think to summarize there's only two main requirements for them to call it ethernet:1.) That the CE handoff is an ethernet interface (usually copper).2.) That it's not routed.
By this I mean not that its not routed on the backend but that said routing is invisible to you and L2 connectivity between locations is possible. If the ethernet is extended between your premise and an MPLS node then of course packets must be routed from that point on and only L3 traffic is possible.EDIT: meant to say CE not PE. MPLS is a way of moving packets around inside a network.