Setting up Port Security Port security is a way to lock down what devices can plug into your switch, or how many devices can plug in. This prevents users from putting switches on their own lines. It is possible to use a specific MAC address and if a new device is plugged in, it will ..
Archives : August-2015
Configuring Passwords on a Cisco Switch The first time you attempt to Telnet, you will be denied because no passwords have been set. Passwords must be set via the terminal: Sw1>enable Sw1#conf t Sw1(config)#enable password PassWord Test the new password by exiting back to User Mode, then attempt to enter Privilege mode. Sw1(config)#exit Sw1#disable Sw1>enable ..
Understanding the Physical Indicators System – System Status. As it powers on, it will blink green. Will turn solid green upon completion. RPS – Redundant Power Supply. If installed, this will glow green. STAT – Default Mode. Show status of port. On (flicker) with signal. Util – Utilization. All lights work together to show full ..
What is the Cisco IOS The Internetwork Operating System A Command-Line method of configuring ANY Cisco Device Software that is consistent through nearly all Cisco Devices Learn it once, use it many times More powerful than any graphic interface Connecting to the Cisco Switch Get a Console Cable Plug the Serial End into the back ..
The Problem with Shared CSMA/CD Carrier Sense Multiple Access / Collision Detection Hubs and Switches perform the same function, but are significantly different. Hubs send all incoming signals to all connected PCs. Hubs work at the Physical Layer, sees the signal and sends it out. Hub Speeds are very fast – Wire Speed. No difference ..
A View of Network Cards on PCs and Cisco Devices Cable Thin Net Would tap into a baseball bat sized with a vampire like connection. Cat-5: Transceiver Category 5: Unshielded Twisted Pair (UTP) Most Popular Higher the Category, the more twists, the more twists, the better the signal strength. Connection: RJ-45 Max Distance: 100 meters ..
The Evolution of Ethernet 1973: Xerox invents Ethernet (3 Mbps) 1982: Ethernet Standardized Between Vendors (10 Mbps) – Prior to this everything was proprietory, so would have to purchase everything from the same vendor. 1995: Fast Ethernet Emerges (100 Mbps) 2000: Gigabit Ethernet (1000 Mbps) 2002: 10 Gigabit Ethernet (10,000 Mbps) 2007: 100 Gigabit Ethernet ..
Bob Packet – The “Local Boy” Bob is a ‘PING’ request that will travel from 172.10.1.20 to 172.10.1.30. Subnet Mask is 255.255.255.0 .20 Compares its Network ID (172.10.1) with that of the Destination IP (172.10.1) and sees they are a match. .20 sends an ARP (Address Resolution Protocol) asking for the MAC address of the ..
How Port Numbers Work Every time an applications communicates across a network, it must decide both the source and destination port numbers. If 10.1.1.1 wants to access 150.1.1.1’s web server, it will use well known port 80. This is written as 150.1.1.1:80 When written in this notation, it is known as a “Socket”. The Source ..
Understanding the Differences Between TCP and UDP Networks communicate in Layers. This is handled in Layer 4, Transport Layer TCP is “Reliable” Reliable – Uses Acknowledgements Builds Connections with system it is communicating with Uses Sequence Numbers – Every packet is tagged with a # to know the order the packets had been sent. UPD ..
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