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Leased Lines vs MPLS

One major difference between the two is that leased lines are generally more expensive than MPLS and can also be more reliable and offer higher bandwidth, because they are not shared. MPLS on the ...
masrad's user avatar
  • 116
8 votes

Is a point-to-point T1 line literally a line in real life?

No. There may be a dedicated circuit between the routers and the nearest telco central office, but between offices they are switched and multiplexed onto other, higher capacity circuits. Today, most ...
Ron Trunk's user avatar
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8 votes
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Why does MPLS use labels to make forwarding decisions instead of destination IP addresses?

I think what you're really asking is, "Why use MPLS instead of traditional routing?" One of the major reasons (probably the reason) people use MPLS is address independence. You can have two ...
Ron Trunk's user avatar
  • 67.6k
7 votes

Difference between WAN and VPN(tunnels)

Originally, WANs were mostly defined by specific layer 1/2 protocols (Frame Relay, HDLC, SONET, etc) that they used, but Ethernet has taken over, and the others are rapidly fading into history. The ...
Ron Trunk's user avatar
  • 67.6k
7 votes

WAN encapsulation

IP packets are encapsulated in a layer 2 protocol, whether they are sent on a LAN or WAN. Frame relay is one such WAN layer 2 protocol. There are others, but most are being rapidly replaced by ...
Ron Trunk's user avatar
  • 67.6k
7 votes

Is a point-to-point T1 line literally a line in real life?

Literally? No. Unless the devices were very close, it's very unlikely they would ever have been directly connected. Even 20-30 years ago, in the era of T1's, there were repeaters, digital cross-...
Ricky's user avatar
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6 votes
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What is a "routable" IP?

What is a “routable” IP? IP addresses can be divided into several categories. Routable on the public Internet. Routable on private networks but not on the public Internet Not routable at all. ...
Peter Green's user avatar
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6 votes
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Error Detection across OSI layers confusion

I know that in the data link layer that is responsible ensuring that frames has been transmitted successfully by sending acknowledgement That is incorrect. There are very few data-link protocols ...
Ron Maupin's user avatar
  • 99.8k
6 votes

Is the Internet essentially a network of routers?

An internet (lower-case "i") is a network of networks. The Internet (upper-case "I") is the largest internet (network of networks). The networks comprising the Internet connect to each other by ...
Ron Maupin's user avatar
  • 99.8k
6 votes

Can a jumbogram (giant data packet) be used at a large scale (in WAN for example)?

Is there any real use of Jumbogram (at least with its minimum payload) at a large scale ? That is actually a good question - I fail to see any real use case currently. The RFC states: Jumbograms are ...
Zac67's user avatar
  • 84.8k
6 votes

How Network layer routing actually works in the physical world

I want to make a few clarifications to @Effie 's answer: The basic idea for this separation, is that each autonomous system can choose how to arrange routing within itself, however routing between ...
Ron Trunk's user avatar
  • 67.6k
5 votes
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SONET/T-Carrier differences - MPLS/VPLS bandwidth

Very briefly, SONET/SDH is a high bandwidth optical WAN technology. T-carrier is an electrical (digital) WAN technology. SONET/SDH is (was) typically used for backbone and inter-provider circuits. ...
Ron Trunk's user avatar
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5 votes
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How does WAN work?

Routers route packets between networks. Routers could have all LAN connections, all WAN connections, or some combination. It doesn't matter, each router interface needs an address in the network ...
Ron Maupin's user avatar
  • 99.8k
5 votes

Public and Private IPs

IPv4 doesn't know anything about public or private IP addresses. To IPv4, they are all IP addresses that can be treated the same. ISPs have agreed not to route packets with addresses in the private ...
Ron Maupin's user avatar
  • 99.8k
5 votes

Map of WAN cables in general

Trivial? I'm not so sure. You'd have to ask many people at many service providers (and in turn their service providers, and then their (dark or lit) fibre providers and then their cabling companies) ...
Marc 'netztier' Luethi's user avatar
5 votes

Why do we need ATM if SONET/SDH can carry IP directly?

SONET is a physical layer protocol (layer-1). You need a datalink layer protocol (layer-2) to handle framing. That was originally ATM, because that was one of the dominant L2's used by carrier ...
Ricky's user avatar
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5 votes
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How Network layer routing actually works in the physical world

I guess this question will require several iterations, so here is iteration 1 Basically, Internet consists of individual networks. Each network belongs to some organization/enterprise/other kind of (...
Effie's user avatar
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4 votes

How do I know my network traffic go through Asia-America Gateway (AAG) Cable System?

There is no way of knowing this for certain. A cable system in and of itself is a Layer 1 connection and does not report any information about itself (even to a traceroute). You may be able to infer ...
Benjamin Dale's user avatar
4 votes
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Unable to properly configure ASA 5512 with WAN IP

You will never be able to ping from the INSIDE interface IP address of the ASA to any OUTSIDE IP address. The ASA does not allow this. interface GigabitEthernet0/0 description Uplink To ComRTR ...
Kanwar's user avatar
  • 56
4 votes
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diff btw PTSN and DSL?

You can't compare those two. They are completely different things. xDSL is a family of point-to-point line protocols which can transport just about any digital data over a few hundred meters to a few ...
Zac67's user avatar
  • 84.8k
4 votes
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WAN lines types - understanding leased line/circuit

A real leased line, could be performed with TDM on a line with for example SDH, TDH or SONET with a CSU/DSU on the customer site (a layer 1 leased line?) This depends - usually a (rare) leased ...
Zac67's user avatar
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4 votes
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What problem does Frame Relay or ATM solve that Ethernet does not?

You're missing a historical perspective. WAN technologies such as frame relay and ATM were created to use existing telecommunications circuitry at a time when everything was based on, and needed to ...
Ron Trunk's user avatar
  • 67.6k
4 votes
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Connecting an SRX chassis cluster to redundant upstream WAN links

If I put two interfaces (one on each SRX) in a reth, is that sufficient to ensure that there won't be any loops? Yes* - reth interfaces are essentially a logical L3 interface - they will not loop ...
Benjamin Dale's user avatar
4 votes
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Same subnet on two firewalls

This is OK. The ISP has issued a /28 subnet and two of those IPs are going to routers. Normally two routers on that subnet would be used for failover, but they could also simply be used as egress ...
Michael D's user avatar
4 votes

load balancing with multiple ISP, one router and asa 5520

If I were you, I would not route the traffic through both the ASA and the RV340. Both devices have similar feature sets (in your scenario), and using both would be redundant. Since you already have ...
user3629081's user avatar
  • 1,008
4 votes

Cisco 892 Low WAN Speeds

Slightly better than 350Mbit/s? That's probably about as good as it's going to get with an 890 series and with NAT. NAT is probably causing the CPU load, here. Don't forget: This product range is ...
Marc 'netztier' Luethi's user avatar
4 votes

WAN encapsulation

Layer 2 Encapsulation covers a number of purposes, most notably framing, error detection, compression, addressing, and protocol layering, and these really apply whether the networking is wide area or ...
jonathanjo's user avatar
  • 16.3k
4 votes

Is the Internet essentially a network of routers?

... nothing but ... No, definitely not. Of course, the Internet is held together by routers, but those routers require a global numbering plan (like unambiguous public addresses), agreed-upon ...
Zac67's user avatar
  • 84.8k
4 votes

Differences between BGP(routing protocols) and vpn mpls?

As @ronmaupin suggests, you are talking about two different things. Routing protocols exchange routing information so that routers can populate their routing tables. They have nothing to do with the ...
Ron Trunk's user avatar
  • 67.6k
4 votes
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Switch vs WAN switch

I would say that nowadays this term is a bit vague. WAN is just a logical role you assign to a device. The backend technology is now 99% of the time Ethernet so in reality, WAN becomes just a logical ...
Danail Petrov's user avatar

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