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5

This is the solution, we need both span and sflow tcam size 256, so i took vPC slice and give it to span region hardware access-list tcam region vpc-convergence 0 hardware access-list tcam region sflow 256 hardware access-list tcam region span 256 Now i am able to use Port-Channel (4x40G bundle) feature sflow sflow counter-poll-interval 30 sflow collector-...


4

There's not really a hierarchy. It's really more of a web. There are national (or international) ISPs that connect to a large number of other ISPs. There are smaller ISPs that connect to only a few other ISPs. Then there are large companies that have their own backbone (Google, Microsoft, Amazon, Facebook, etc). There's no "rule" about who can ...


3

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.


3

It's important to understand that the cases where auto-negotiation should be disabled ARE VERY RARE. Many times study material for tests are a bit out of date. Virtually all equipment manufactured in the last 20 years is fully compatible with auto-negotiation. As @zac67 and others have pointed out, early implementations had some incompatibilities. But ...


3

With rare exceptions, disabling Auto Negotiation is not a good idea. Auto Negotiation (AN) is mandatory for 1000BASE-T and faster. It should stay enabled generally. Disabling it makes a default node (configured with AN) fall back to half duplex - so forcing 100M full duplex on one side causes a link partner with default configuration to connect using 100M ...


2

How does my computer and x.x.x.x know how to talk to each other? If I use a human messengers analogy, I would tell a person to go get me a package, and I would give him the address of the location and a map (he probably already have one). Exactly, an IP packet has both the source and destination IP addresses on it, much like the envelope of a letter. You ...


2

Rather simple: each direction has its own and independent sequence number and sliding window. So, whether the ends are sending data unidirectionally (one end just ACKing with otherwise empty segments) or bidirectionally doesn't matter.


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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 "...


2

There are various representations for ifSpeed. Basically, some use bit/s, some use Mbit/s, or even kbit/s. Make sure you use the correct magnitude. Also, usage is current throughput divided by link speed, e.g. you measure 2 Gbit/s for a 10 Gbit/s link, resulting in .2 or 20% utilization. The formula in your question is correct, but the correct bracket ...


1

How does my computer and x.x.x.x know how to talk to each other? They don't really. But they know who to ask. Routing is a collective effort. Most routers gateways only know a small number of other routes and gateways. Only few routers need to know all routes. A greatly simplified view: Your computer sees by the destination IP that the destination is ...


1

(This will tread on "historical trivia") The tiered construct was the original vision of the ARPANet (what became the internet.) The modern internet does not work like that. In fact, the early internet -- and ARPANet before it -- didn't entirely work like that either. With the advent of BGP, any network could be anywhere, connected to anyone. ...


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Yes. An increase in path cost only means that the path may be less preferred than another (or it may be the only path). If the route is still in the routing table, the router will still forward the packet.


1

can we still transfer packets between the two routers? Yes. But your network might not work efficiently or at all. Basically, most routing algorithms in practice use Dijkstra's algorithm (OSPF, IS-IS, SPB) which is faster to converge. Any router can only use the information that is has gained access to - effectively, until the network has converged, there's ...


1

That depends on whose definition of socket you use and in some cases whether the packet is opening a new connection or transferring data for an existing connction. The RFC that defines TCP defines the term socket as a combination of an IP address and a port. By this definition the two packets have the same socket on the server side but different sockets on ...


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