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15

I can see two possible explanations: Your WAN address is your public address, but you are yourself using something that makes it look like you are accessing the internet somewhere else. One example is a proxy server which uses the 182-address to access the internet. A website telling you what your public IP is would see the 182 address. Often these sites ...


8

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 term "WAN" now generally describes a network that covers some larger geographical area than a LAN. Sounds vague? It is. Some WANs, like the Internet are public,...


8

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 T1 circuits are emulated over a packet-switched (IP) network. They are rapidly becoming obsolete, and are being replaced by SIP over the IP network.


7

If you are using the same provider for your primary and backup MPLS connections, it is almost a certainty that they are the same network. Even if you were to use a different technology for your backup links (e.g, frame relay), the provider would likely provision that over their MPLS network. I know you want a simple answer, but your question is pretty ...


7

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 Ethernet. On LANs, of course, you have Ethernet and Wi-fi. MPLS doesn't quite fit into the TCP/IP or OSI model. Some consider it a "layer 2.5" protocol.


7

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-connects, and multiplexing into larger T-carriers. As Ron has said, today the T1 is a relic. It will be emulated and carried as packets like every thing else "...


6

There are many things that can cause low SNR. If you put aside natural reasons such as attenuation caused by distance, most of the time problem lies in bad infrastructure. Bad cables (damaged shielding and exposed wires), ingress noise, crosstalk, impedance mismatches, bad connectors and micro-reflections, bad splitters and filters and stuff like that. It ...


6

Wikipedia is your friend: LAN: A local area network (LAN) is a computer network that user interconnects computers in a limited area such as a home, school, computer laboratory, or office building using network media. In simple words, what unifies devices on one LAN: they are situated in the same area. Most commonly, one LAN is behind one router (not ...


6

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 that do this. The transport protocol is normally where acknowledgement takes place, but not all transport protocols do that. TCP does, but UDP does not. With a ...


6

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 agreement of the network owners (companies) using BGP as the routing protocol. IP stands for Internet Protocol. Layer 3 of the OSI model (IP) is the lowest layer ...


5

There is no 'technical' difference. Traditionally they used quite different networking technologies although that is becominging less and less the case. The vague distinctions are that a LAN is in one local area, with lower latency, always connected, generally controlled by a single body, a WAN is spread over a distance and expected to have higher latency ...


5

Fundamentally, loss of signal and/or increase in noise. If your SNR is always low and has always been low, it may simply be near the distance limit. Then again, it could be that it's always run over a lousy chunk of cable or bad splice. A few years back I had two ADSL circuits to campus, which took different routes - one significantly longer. Both cost the ...


5

You are probably better off with not using NAT for the server. I don't know how to configure the Draytek, but your Juniper SRX is certainly able to do the following: Your WAN address of the router/firewall is 213.x.x.254/30 The default gateway of the router/firewall is 213.x.x.253 Telenet will route 82.x.x.16/29 to 213.x.x.254. From the /29 subnet you will ...


5

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. People often say "routable" when they mean "publically routable" and "non-routable" when they mean "not publically routable" ...


5

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. T-carrier is (was) used for lower bandwidth leased lines for subscribers. SONET bandwidth typically starts at around 150Mb and goes up to 10Gb. T-carrier ...


5

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 connected to that interface. Because routers route packets between networks, each router interface is in a different network. The terms "WAN" (Wide Area Network) ...


5

Wan links are provided by service providers wan links are point to point link link a physical cable is connected between both end points .consider to be highly secure no other intruder can access this links it's private lieased link Where as vpn tunnel is build between two different organisation on different locations. Data is encrypted and forward towards ...


5

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 IPv4 ranges (and other ranges, too) between each other. Your packets destined to the public Internet will have public addressing on the source of the packets, and ...


5

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) about many many details, most of which they won't, can't or must not make public. You might be able to get some high-level diagrams (as in: a powerpointable ...


5

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 networks. (vs. frame relay, ATM easily mixes voice and data.) IP (layer-3) "directly" over SONET still needs framing. Packet-over-SONET (POS) uses PPP (...


4

Here is a decent explanation from DrPeering.net of the cost per bit-mile(meter). The Simple Bit-Mile Costing model tries to establish a network component price per bit mile. This calculation might take all route segments and calculate the average cost per mile. The end result would be a $/bit mile cost number. Then gross traffic analysis would be ...


4

One option is to connect both switches together and create two vlans that span across both switches. Connect the routers and the WAN side of the FW to VLAN 1. Connect the LAN side and the servers to VLAN 2. If you run HSRP on the routers, that is your default gatewway for the firewall. Here is a logical diagram. Let me know if you need help configuring ...


4

I’m trying to understand what you’re asking, and based on how you described the network setup, there isn’t any good reason to use private addressing; even if you need to use separate network for other functions. The link you provided in the comments advertises that it handle multiple subnets. I would start with setting your Draytek Vigor up as a DHCP ...


4

Does my default WAN port need to connect to a WAN port? No, you don’t need to. WAN, in this sense, is just blocking inbound requests by default. I’ll assume the reason you’re using pfSense is to perform routing functions between those 2 networks (?). If you aren’t using it for any real firewall functions, then you would be alright to, technically, just ...


4

@PHLiGHT, hello there! your cisco 861, imho, has overloaded by ingress traffic. Lets look on your cisco iface counters: 5 minute output rate 198000 bits/sec, 56 packets/sec 157099395 packets input, 3610517494 bytes Received 1 broadcasts, 76 runts, 0 giants, 655 throttles 338 input errors, 0 CRC, 0 frame, 149 overrun, 189 ignored you have 655 ...


4

To calculate the number of links in a fully meshed topology of N devices, the formula is this: Full-mesh links = (N)*(N-1)/2 Substituting numbers... = 40*39/2 = 780 However, you'd only have one link to every switch if calculated thusly. If you assume 4 links per switch, it's technically 4*780, or 3120 uplinks.


4

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 connectivity from the name resolution of hops along your traceroute, but you could never prove this (there may be multiple cable systems between the two end ...


4

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 nameif outside security-level 0 ip address 50.78.73.50 255.255.255.240 The OUTSIDE interface is connecting to the 50.78.73.48/28 subnet. The route command is ...


4

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 kilometers, especially various packet-switched or virtual-circuit network protocols. PTSN is a generalized term for a circuit-switched, analog/digital hybrid ...


4

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 physical line is just copper or (dark) fiber. It's up to you what you do with it. A leased circuit could be done with a ATM CPE on the customer site, typically ...


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