Questions tagged [ethernet]
For questions relating to Ethernet networking, as defined by the IEEE 802.3 standards.
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Can you guys help me to find which router is this? [closed]
It has serial, fastethernet and ethernet port.
s0/0 f0/0 and e1/0
It try to use c7206 but it adds the serial s1/0 not s0/0.
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What is the practical use of bandwidth-delay product? [duplicate]
It's given that the bandwidth-delay product defines the number of bits that can fill the link; while the sender can send (1+(2 * Propagation Time / Transmission Time)) units before getting ...
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Cat5 Ethernet cable between buildings passes connectivity test but switch light not lighting up and no connectivity
I have a 2 buildings about 25 metres apart and there is a cat5 ethernet cable encased in a pipe between the 2 buildings. Just suddenly the connection stopped working. If I test the cable with a ...
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Just testing a 2 pair twisted internet cable having 4 wires [duplicate]
I am having a problem with my 2-pair ethernet cable. I have connected the 4th, 5th, 7th, and 8th pins, but the 4th pin is not working. I have checked the RJ45 connector and the cable with a multimeter,...
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1
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OVS pop_mpls action returning invalid ethernet frames
I am currently running into walls when trying to pop an mpls label with ovs.
I currently have two interfaces on one ovs instance connected to ports eth0 and eth1. I define a flow on eth0 to pop an ...
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54
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Negotiate at 10 Gbit/s but gain lower speeds due to issues?
During the autonegotiation process, network devices communicate and determine the highest mutually supported data rate. In the case of a network adapter supporting both 10 Gigabit per second (10Gb/s) ...
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Ethernet frame's source mac-address out of a port in an ARP request forwarded to an interconnected switch towards an end host
PC1 ----- (P1) SWITCH1 (P2) ----- (P2) SWITCH2 (P1) ----- PC2
Assume two network switches SWITCH1 and SWITCH2 are interconnected to each other through their ports P2 respectively present on each ...
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2
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How to connect HP 2930-8g to the cisco CBS350-8g switch unmanaged?
I want to Connect HP 2920-8g to CISCO CBS350-8g. I tried HP sfp ( J4859D ) in HP and CISCO working fine,
with HP and Cisco switch and cico sfp (MGBLX1) and programmed
switch(config)# allow-...
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1
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106
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Calculate Ethernet frame [duplicate]
I have a couple of confusing problems on my course, so I decided to ask here.
The question is:
What is the minimum size of Ethernet frame for a network speed of 100MBps* and maximal segment of 100 ...
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3
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78
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same rack connection: better RJ45 or SFP?
For a connection between two devices on the same rack:
Is there any notable difference or advantage between using 1Gb SFPs and using Gb Ethernet ports? (making a bonding/etherchannel).
I know for ...
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1
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101
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IP and Ethernet endianness
I'm completely new to the topic, I've read that Ethernet sends Bytes in a Big-Endian way, but that bits are sent with Little-Endian. I've also read that IPv4 uses Big_endian order. So my question is, ...
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2
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112
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Is there a way to find all MAC addresses in an Ethernet network?
How can I find all MAC addresses connected to a LAN network? Is there a way or protocol to do this?
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Camera instead of ethernet cables
My electricians messed up and installed some sort of camera (or very old cat3?) cables, instead of the requested ethernet cables (see picture). Now I have two of those, running for about 15 meters ...
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73
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Reach IP in a different subnet
I have two Ethernet devices:
One is 10.1.1.10 with a netmask set to 255.0.0.0
The other is 10.255.253.5 with a netmask set to 255.255.255.0
Why can't I reach the second device from the first one (...
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How does each OSI layer get to know the information [duplicate]
This might sound dumb but how do each layer get the information?
To give a context,
Lets say I enter www.google.com, the browser sends a request to the Application layer and then the HTTPs request is ...
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2
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408
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Adapting 10GBaseT and NBaseT with a PoE Injector?
Suppose I have a device that supports 10/100/1000/10GBase-T ("Firewall") and another device that supports 10/100/1000/NBase-T ("Modem").
Now, I could connect these two devices ...
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iSCSI silent data corruption
I came across an interesting table with estimations of silent data corruption rate for different interfaces. SAS shows the best result when the built-in integrity control (DIF) is enabled:
Interface
...
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2
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100Mbps embedded device on a GbE network.. can I use MII?
Newcomer to Networking. I would like to connect an embedded device to an existing Fibre Gigabit LAN. The device would source and sink very little data so I am considering my choices.
A ...
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1
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Slim Ethernet 28AWG Length Limitation question for IDFs
anyone have experience with the slim ethernet cabling? I see a lot of atricles stating they are limited to around 30ft. Does this footage include the in-wall cat6 run from Patch panel to Desk drop? ...
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Confusion between MDI and MII
Media Dependent Interface
Media Independent Interface
My understanding is 2. is an interface between PHY chip and MAC block on the board. PHY chip can be on the board, or detachable. It is rather PHY ...
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149
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Network connection into a Faraday cage
I have a situation where I need to put a WiFi-only IoT device inside a radiation-shielded space in which the facility WiFi doesn't work. (Even outside the shielded space the WiFi barely works, due, I ...
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3
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Wifi solution to connect two warehouses on to same network
I’ve just acquired a second warehouse however it’s approx 100m from my current one.
To save me the headache of having two wifi systems what’s the best solution to bring my current wifi network into my ...
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Is it possible to establish communication using just an ethernet cable?
I have two linux systems, server and client, whose both ethernet port has VLAN tagging(preconfigured IP address and same subnet), and connected with a common ethernet cable (no router or network ...
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2
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149
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Connecting L3 and L2 switches with VLAN settings
I have 1 L3 switch with
Static ip - 192.168.0.252
Two L2 switches
Switch A - 192.168.0.250
Switch B - 192.168.0.251
I have created VLANs in L3 switches with 192.168.1.1 and 192.168.2.2 ips abd set it ...
- 101
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2
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174
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Degradation of signal quality as a function of cat 6 cable length
I would like to make a run of cat 6 ethernet cable between 2 dwellings, underground. It appears I may need just a little over the maximum length for 1 Gbps (100 meters), maybe 110 meters or so. ...
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9
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Why can I send 127.0.0.1 to 127.0.0.0 on my network?
We have a product that runs over IP. This product comes in two halves that are supposed to be connected directly to each other over Cat 5e. All this works fine.
For reasons that are not important, we ...
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71
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I can no longer access my Dell EMC N1124T-on through its GUI interface
We configured and set up our Dell EMC with a Putty interface first and went through the Set up wizard and gave it a static IP. Then joined it to our network and Deployed it into our IDF. Accessed it ...
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What components of a network switch qualify as ASICs?
While studying for CCNA, I came across the information that in a network device, say a switch, the CPU is responsible for the control and management planes work, while the actual data forwarding is ...
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What is the loopback Ethertype?
IANA's list of IEEE 802 Ethertypes includes an entry for Loopback (0x9000). However, I cannot find any specification detailing exactly how this is implemented. Do frames sent with Ethertype 0x9000 ...
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2
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2
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281
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POE injector to extend the number of devices
I have a networking problem. I have a network that runs of a POE switch that is routed to a relatively deep chain of POE powered switches that also passthrough POE. The problem becomes that the load ...
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159
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Why are the pins in this RJ45 port not all identical?
As shown on the picture below, the pins on these Ethernet ports are not all the same.
It looks like pin 3, 5, 7 and 8 (or 1, 2, 4 and 6?) are elevated in order to make contact, but not the others.
I'm ...
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Which Ethernet cable should l use to connect two office buildings?
I am an extreme newbie in real networking. I have developed an application for our internal office management which is to be installed on 4 machines. One of the offices is in another building around ...
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Are switch MAC address tables only filled when the end devices sends the frame rather than receiving? [duplicate]
So I am going through the Cisco Network Academy courses and recently watched their video about how an ethernet switch's MAC address table is populated. If there are 3 hosts connected to the switch, ...
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2
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Alternative Solution to Avoid Loop aside STP
SITUATION: I have two switches SW1 and SW2. These two switches are connected with two trunk ports. While SW1 is connected to PC1, SW2 is connected to PC2.
If PC1 sends a broadcast frame to PC2 via ...
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SFP28 port and SFP module (not SFP+)
I'm about to buy a device that has some SFP28 ports. I know that SFP28 is backward compatible with SFP+. But I want to know its backward compatibility with the SFP module.
Can I use an SFP module (...
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1
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576
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How to connect GNS3 to loopback adapter on Windows 10
I'm trying to have a simple topology by connecting a router (c7200) and the local machine which is windows 10. For this I use GNS3 GUI (not the VM application). I have to do that, due to the limit of ...
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3
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Could Ethernet collisions be avoided using multiplexing?
I know that multiplexing can be used to combine multiple analog or digital signals over a shared medium. Thinking about it I was wondering why we can't use this technique to avoid collisions in ...
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Will the UDP packets reach its destination?
I am trying to send UDP Packets using Linux Socket.
Working inside a Linux VM.
Server IP = 172.16.x.x
Client IP = 172.21.x.x
Both are connected via a Ethernet switch.
Doing a broadcast on company's ...
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1
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170
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MAC OUI in Bits 3 to 24
One networks basics course the statement was made by lecturer for OUI (Organizational Unique Identifier) to be carried in MAC-address Bits 3 to 24. I wonder where the start bit number 3 from? It is ...
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2
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1
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176
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What is Ethernet MDI in the case of SFP interfaces
I am reading on Ethernet and I understand that for copper ports, the MDI is the physical connections from the PHY to the medium's connector, including the physical port itself, where the cable is ...
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Can a jumbogram (giant data packet) be used at a large scale (in WAN for example)?
There are many scientific paper for Jumbo frame, even more, some real implementations and deployments. But it is not the case for Jumbogram !!
Jumbo frame (geant frame) for Layer 2; Jumbogram (geant ...
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171
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can we use RJ45 with cat7 sftp?
I am currently working on connecting ip cameras together .
I am using cat7 sftp cable .
according to the bellow article :
http://www.differencebetween.net/technology/difference-between-rj45-and-rj48/
...
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1
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406
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Does Ethernet have a header and a trailer?
I have read that Ethernet have a header and a trailer, but in Wireshark I can only see an Ethernet header and no Ethernet trailer.
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Length of Ethernet Preamble on 10Gb network
I know (see https://en.wikipedia.org/wiki/Ethernet_frame) that an Ethernet frame includes a 7 byte preamble of 0x55s and a one byte start frame delimiter (SFD) 0xD5, for a total of 8 bytes before the ...
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3
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Is it called the "MAC" protocol or the "Ethernet" protocol?
I know that there are protocols called the TCP protocol and the UDP protocol and the IP protocol, but what is the protocol at the data link layer in Ethernet called? is it called the "MAC" ...
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How to enable ip address for all ports in the Cisco IOS Web Browser
Good afternoon, how do i enable the ip address in webui for the cisco switch you can see the picture below ipv4 is unassigned, everything looks good with me.
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How can I connect 1000BASE-SX (multi-mode fiber) to 100BASE-TX/10BASE-T (copper)?
How can I connect an optical 1000BASE-SX SFP optical transceiver to a microcontroller (MCU) with 100/10BASE-T? When using a media converter like DP83869 both sides of the link must be configured to ...
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1
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53
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What is an Ethernet Network Switch Port
I am trying to understand what an Ethernet Switch internally considers a single port.
My current understanding is that when a seller advertises an Ethernet Network Switch, like the one below, has five ...
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3
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512
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How do we discover hosts on another subnet without knowing their IP or MAC address
If I have a client who wishes to send a UDP packet to another client, how would I scan for his IP address if Client 2 is located in another subnet?
If I'm trying to discover clients on my own subnet I ...
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2
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80
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Why is a PoE circuit limited to 328 feet?
I'm trying to learn about PoE and a friend told me the 100 meter limitation on a PoE circuit is because of the DC voltage drop on the power channel, not the data. I had understood the opposite, that ...
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