Tech Blast: NetworksMichael Sauers

Tech RodeoDoane College, 26-28 July 2012

Router

A router is a device that forwards data packets between computer networks, creating an overlay internetwork. A router is connected to two or more data lines from different networks. When a data packet comes in on one of the lines, the router reads the address information in the packet to determine its ultimate destination. Then, using information in its routing table or routing policy, it directs the packet to the next network on its journey. Routers perform the "traffic directing" functions on the Internet. A data packet is typically forwarded from one router to another through the networks that constitute the internetwork until it gets to its destination node.

SwitchA switch is a telecommunication device which receives a message from any device connected to it and then transmits the message only to that device for which the message was meant. This makes the switch a more intelligent device than a hub (which receives a message and then transmits it to all the other devices on its network.) The network switch plays an integral part in most modern Ethernet local area networks (LANs). Mid-to-large sized LANs contain a number of linked managed switches. Small office/home office (SOHO) applications typically use a single switch, or an all-purpose converged device such as a residential gateway to access small office/home broadband services such as DSL or cable internet.

Ethernet Cables

• Cat-5– 10 or 100 Mbps

• Cat-5e– Up to 1 Gbps

• Cat-6– Up to 10 Gbps

Networking Protocols

• TCP/IP– IP address– Internal vs. External– Dynamic (DHCP) vs.

Static• DNS

– Domain Name Server• HTTP/HTTPS

• SAMBA– Used for communicating

between Linux & Windows computers on a LAN

WiFi

• Versions– b (up to 11 Mbps)– g (up to 54 Mbps)– n (up to 150 Mbps)– ac (up to 866.7 Mbps)

• SSID– Service Set Identifier

• Security– WEP– WPA

WiFi Continued

• Distance matters• Channels• Access Points /

Repeaters / Extenders

Power Line Networking

Power line communication (PLC) is a system for carrying data on a conductor that is also used for electric power transmission.

200 or 500 Mbps

Firewall

A firewall can either be software-based or hardware-based and is used to help keep a network secure. Its primary objective is to control the incoming and outgoing network traffic by analyzing the data packets and determining whether it should be allowed through or not, based on a predetermined rule set. A network's firewall builds a bridge between an internal network that is assumed to be secure and trusted, and another network, usually an external (inter)network, such as the Internet, that is not assumed to be secure and trusted.

NAS

Network-attached storage (NAS) is file-level computer data storage connected to a computer network providing data access to heterogeneous clients. NAS not only operates as a file server, but is specialized for this task either by its hardware, software, or configuration of those elements. NAS is often made as a computer appliance – a specialized computer built from the ground up for storing and serving files – rather than simply a general purpose computer being used for the role.

Thanks!Michael Sauers

michael.sauers@nebraska.govdiane.r.wells@nebraska.gov