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Importantly, you do not need to write software that runs on network-core devices, such as >routers or link-layer switches. Even if you wanted to write application software for these >network-core devices, you wouldn’t be able to do so." Even these lines are being blurred today. There are some companies with "software" routers and they ...


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Cisco IOS commands are only in English. You can get manuals and datasheets in other languages.


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On some devices, a routed L3 interface may require less hardware resources (from TCAM) than a VLAN plus SVI. A routed port can enable you to re-use the same VLAN ID from another L3 port or from an L2 VLAN without any risk of L2 traffic in between. A routed port may be easier to manage by an admin, especially with ECMP or similar (no need to twiddle with MSTP ...


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Yes, most often. It depends on how exactly your ISP connects your IP addresses into their network. Usually, you're given a subnet where one IP address is used by their router - e.g. 192.0.2.32/28 with the router on .33, and .34 through .46 for you to use. You can then connect a firewall and map those addresses into your network, but you can just as well ...


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Just to muddy the waters even further, the routing function ( forwarding packets) happens at layer 3. But many routing protocols, like BGP and RIP, run in the application layer. OSPF and EIGRP are applications too (sort of) but they don’t quite fit into OSI or TCPIP model.


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You should make a difference between router function and a router appliance. The router function is located in the network layer. A router receives packets and forwards them between networks based on their destination addresses, according to its routing table. A router appliance's main function is routing. Additionally, it may support all kinds of additional ...


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It is said that layer 3 devices such as routers do not have an application layer. No, routers route at layer-3, not the application layer, but that does not mean a router cannot have a user interface in the application layer. But whenever I want to configure my home router I punch in the IP address and open up its graphical user interface. Home networking ...


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192.168.1.0/24 via 192.168.3.2 That's why. Router 2 uses 192.168.3.2 as a gateway to 192.168.1.0/24, including 192.168.1.2. The router doesn't know (nor care) that there's no gateway behind that IP address. Instead, Router 2's gateway towards 192.168.1.0/24 needs to point to Router 1's IP address on Gig9/0. Router 1 requires routes to networks #2-#4 (and ...


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The queue filling is a natural effect of Data Transmission protocols such as TCP(connection based) which has a send buffer of data on the client, which get filled and then released onto the network. before more data can be send, the sender needs to waiting for acknowledgement of the data from the receiver, causes an high/low traffic fluctorion of the ...


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I don't have that book, but I suspect what he's getting at is is that, while the average arrival rate may equal the maximum transmission rate, there can be fluctuations in the arrival rate. When the arrival rate fluctuates above the transmission rate, the queue fills up (assuming it doesn't drop packets). When the arrival rate fluctuates below the max ...


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Very obviously, when the ingress rate exceeds the egress rate (that "traffic intensity" exceeds 1) you've got exactly two options: queue the data (with the hope to catch up when the ingress rate slows down again) drop the data (and have someone else clean up the mess) Neither method is the always-right solution. You can't queue indefinitely (...


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WAPs send beacon frames to the STAs, and the STAs can send probe frames. This is all part of the 802.11 standard used by Wi-Fi. Remember that the protocols you are referring to are layer-3 or above protocols, but 802.11 defines the physical (layer-1) and data-link (layer-2) protocols.


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Wireless access points transmit periodic beacon frames to announce the presence of wireless networks.


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