aurmol 0 Posted December 15, 2014 I've been confused something about this for 2 days and been searching in the net but some things are just not clear. A switch handles MAC and not ip addresses. A router handles ip addresses. First question. If you have 3 computers connected with switches and say with ip address 192.168.1.101, 192.168.1.102, 192.168.1.103, how come you can access using computer 1 (with ip 192.168.1.101) the computer 3 (with ip 192.168.1.103) using just the ip address? I thought switch can't deal with ip addresses but only mac address. Second and main question. If you have an NVR and ip cameras. How come you can connect the ip cams on the switch with the NVR plug into the switch too (without any router present) and the NVR can recognize or find the ip addresses of the ip cams? I thought Switches just deal with MAC address? It's one big mystery with answers that can't be found in the net. Anyone has a clue why? Share this post Link to post Share on other sites
ak357 0 Posted December 15, 2014 I've been confused something about this for 2 days and been searching in the net but some things are just not clear. A switch handles MAC and not ip addresses. A router handles ip addresses. First question. If you have 3 computers connected with switches and say with ip address 192.168.1.101, 192.168.1.102, 192.168.1.103, how come you can access using computer 1 (with ip 192.168.1.101) the computer 3 (with ip 192.168.1.103) using just the ip address? I thought switch can't deal with ip addresses but only mac address. Second and main question. If you have an NVR and ip cameras. How come you can connect the ip cams on the switch with the NVR plug into the switch too (without any router present) and the NVR can recognize or find the ip addresses of the ip cams? I thought Switches just deal with MAC address? It's one big mystery with answers that can't be found in the net. Anyone has a clue why? http://lmgtfy.com/?q=computer+networking+101 http://lmgtfy.com/?q=what+is+network+router http://lmgtfy.com/?q=what+is+network+switch Share this post Link to post Share on other sites
aurmol 0 Posted December 15, 2014 I've been confused something about this for 2 days and been searching in the net but some things are just not clear. A switch handles MAC and not ip addresses. A router handles ip addresses. First question. If you have 3 computers connected with switches and say with ip address 192.168.1.101, 192.168.1.102, 192.168.1.103, how come you can access using computer 1 (with ip 192.168.1.101) the computer 3 (with ip 192.168.1.103) using just the ip address? I thought switch can't deal with ip addresses but only mac address. Second and main question. If you have an NVR and ip cameras. How come you can connect the ip cams on the switch with the NVR plug into the switch too (without any router present) and the NVR can recognize or find the ip addresses of the ip cams? I thought Switches just deal with MAC address? It's one big mystery with answers that can't be found in the net. Anyone has a clue why? http://lmgtfy.com/?q=computer+networking+101 http://lmgtfy.com/?q=what+is+network+router http://lmgtfy.com/?q=what+is+network+switch Done it for 2 days. But it doesn't answer what is the difference if you connect the NVR to a switch together with other ip cams or if you connect the NVR to a router and switch with ip cams connected to that router.. what is the subtle difference in the packeting? Do all NVR search for ip cams by the MAC address or ip address? and if ip address.. but a switch doesn't have any ip address capability.. just MAC.. so herein lies the big mystery Share this post Link to post Share on other sites
gb5102 0 Posted December 16, 2014 I've been confused something about this for 2 days and been searching in the net but some things are just not clear. A switch handles MAC and not ip addresses. A router handles ip addresses. First question. If you have 3 computers connected with switches and say with ip address 192.168.1.101, 192.168.1.102, 192.168.1.103, how come you can access using computer 1 (with ip 192.168.1.101) the computer 3 (with ip 192.168.1.103) using just the ip address? I thought switch can't deal with ip addresses but only mac address. Second and main question. If you have an NVR and ip cameras. How come you can connect the ip cams on the switch with the NVR plug into the switch too (without any router present) and the NVR can recognize or find the ip addresses of the ip cams? I thought Switches just deal with MAC address? It's one big mystery with answers that can't be found in the net. Anyone has a clue why? The answer to your mystery is Address Resolution Protocol http://en.wikipedia.org/wiki/Address_Resolution_Protocol Share this post Link to post Share on other sites
jazzar 0 Posted December 19, 2014 I think that most NVR's that use discover devices use the MAC address to find their own models of kit on the network (the first 3 octets are unique to a manufacturer) some also allow you to add in ip addresses of other manufacturers if they allow onvif type devices to be used on the NVR for example. As the packets of data are sent around the net the ip addresses are stripped off and the data is forwarded via the MAC address from point to point. You are getting into the root level of network transmission and the OS model to understand this. Plenty of online self learning info available- and university courses that last up to 5 -7 years to get qualified to the N'th degree in the technology so only the basic concept can be given in a short answer. Share this post Link to post Share on other sites
ericq 0 Posted December 22, 2014 First off - 10,000ft overview - difference between a switch and router. Switches work on the Local Area Network (LAN) and connect similar type networks Ethernet/Fast Ethernet/Gigabit Ethernet (10/100/100). Ethernet switches connecting to each other and they use MAC addresses (Layer2). (yes unless you have a layer 3 switch) Routers connect dissimilar type networks for LAN or Wide Area Network (WAN) type connections. Think Ethernet to the Internet which would be a WAN type connection like T1, T3, Cable, DSL or it could even make a conversion from Ethernet to older technologies like Token Ring, FDDI, ATM, etc.. Routers can also act like a traffic cop say your network isn't going to reach my other local network. To answer you first question Every Network Interface Card (NIC) has a different MAC address as it is hard coded into the NIC. As GB5102 mentioned Address Resolution Protocol (ARP) is a protocol that translates IP and MAC address and is used by the switch. Lets say you turn on a brand new switch and .101 computer (pc) on port 1 with MAC address AAAA wants to talk with .103 pc on port 3 with a MAC address CCCC then .101 pc sends the request/packet to the switch. The switch looks at the packet received and sees it came from port 1 with a source MAC address of AAAA a destination of CCCC. It checks it's MAC table to see if it has AAAA listed yet. If it does not, it adds it to it's mac table for MAC address AAAA on port 1. Then the switch does a lookup in it's MAC table for address CCCC to see if it knows what port CCCC is on. If it does not find it then the packet is flooded out all ports except the originating port. The switch now knows what port MAC address AAAA is on, so if it receives traffic for AAAA it will only send it to port 1. When .103 pc with MAC address CCCC replies to AAAA the switch sends the traffic only out port 1 and it will also add an entry for MAC address CCCC - port 3 to it's table. Second question see answer to question 1. Hope this helps. Share this post Link to post Share on other sites
