Wireless Networks: Networking basics and understandings (Compilation) - Printable Version +- howtothings.co.uk (https://www.howtothings.co.uk) +-- Forum: Computing (https://www.howtothings.co.uk/forumdisplay.php?fid=4) +--- Forum: Hardware, Networking and Wireless (https://www.howtothings.co.uk/forumdisplay.php?fid=11) +--- Thread: Wireless Networks: Networking basics and understandings (Compilation) (/showthread.php?tid=750)

Wireless Networks: Networking basics and understandings (Compilation) - Mark - 12-02-2011 Wireless Networks: Networking basics and understandings (Compilation) This is going to be a small part in the soon to come networking threads and tutorials that I am creating. Anyone that asks me receives the same answer about networking, I believe that it is vital to understand how a network works and the key technologies in place if you are working with computers, it'll also put you at a massive advantage as everything these days is joined to some sort of network yet many people I've come across do not understand how things work, how to troubleshoot etc. In this first thread I decided to go with something that most of us use daily and something that's constantly around us and if not secured properly, something that can become a massive security flaw to a network. Disclaimer This thread has been created off the top of my head with a brief look or two at notes and it's for networking basics, I describe the technologies being used it's then up to you if you want to go further on your own to understand how they tick. This truly is skimming the water. Feel free to correct me or offer the addition of anything. If you read and understand all of the documentation that I create, at the end you'll be able to easily pass exams such as the CompTIA Network + The CompTIA Network+ certification is the sign of a competent networking professional. It is an international, vendor-neutral certification that proves a technician’s competency in managing, maintaining, troubleshooting, installing and configuring basic network infrastructure. Number of questions: 100 Length of test: 90 minutes Passing score: 720 on a scale of 100-900 Recommended experience: Nine months networking experience Exam codes: N10-004 and JK0-016 Wireless communication standards Wireless is being used more and more lately. In this section I will discuss the most common standards and how they're used in today's networks. Wireless LAN technology is specified by the IEEE specification 802.11. There are four main standards in use today. 802.11a Frequency: 5GHz Speed: 54Mbps This standard is not widely used today. 802.11b Frequency: 2.4GHz Speed: 11Mbps Has fall-back rates of 5.5Mbps, 2Mbps and 1Mbps. 802.11g Frequency: 2.4GHz Speed: 54Mbps I'd say this is still the most used standard today and it's backwards compatible with 802.11b. 802.11n Frequency: 2.4GHz/5GHz Speed: 600Mbps The newest wireless standard, it can support up to 600Mbps although most devices used today can only utilise 300Mbps. Backwards compatible with both 802.11b and 802.11g. 802.11b, g and n all use direct sequence spread spectrum (DSSS) Devices operating in the 2.4 GHz range include: microwave ovens, Bluetooth devices, baby monitors and cordless telephones which can cause interference on wireless networks. Wireless Encryption Wireless security is a big concern, there are 4 main standards in use today. Wired Equivalent Privacy (WEP) This is the least secure of all wireless encryption. Keys are either alphanumeric or hexadecimal and can be 40-bit, 64-bit, 128-bit, 153-bit or 256-bit. If you're interested you find can one of my threads here: How to crack WEP Wi-Fi Protected Access (WPA) WPA was designed to improve upon WEP, while it is more secure it's still crackable. Uses Temporal Key Integrity Protocol (TKIP) encryption. (128-bit encryption) There are two modes to WPA, WPA Personal and WPA2 Enterprise. WPA personal uses pre-shared keys (PSK). PSKs or passphrases can be up to 63 characters long and a minimum of 8 characters. WPA Personal is often used in SOHO networks. WPA2 Enterprise uses 802.1x authentication servers and is often used in corporate / enterprise environment for heightened security. Wi-Fi Protected Access Version 2 (WPA2) WPA2 uses Advanced Encryption Standard (AES), (256-bit encryption) but can also be used with 802.1x servers or PSK. WPA2 Personal uses AES-PSK, passphrases can be from 8-63 characters long. WPA2 Enterprise uses 802.1x authentication. Remote Authentication Dial-In User Services (RADIUS) RADIUS provides centralised authentication. Users can be authenticated to use a wireless connection through a RADIUS server which authenticates using the current logged on user which must have an account in the domain. RADIUS is commonly used in enterprise environments. Wireless Hardware Router Basically a router forwards traffic (packets) from one network to another, whether this is between subnets or from your LAN to the internet. You can get both wired and wireless routers. Routers work at layer 3 of the OSI model. (We've not covered the OSI model yet) Wireless Access Point (WAP) A wireless access point is connected to an existing wired network, anyone that connects to the wireless will become part of the wired network. WAPs are commonly used to extend the range of an existing wireless network, if you wanted to get wireless in the garden or at the other side of a large house then you'd use a WAP, not another router, (unless it was in WAP mode). Wireless Cards Clients can connect to wireless networks using a variety of wireless cards, including PCI, PCMCIA, USB or built in. Addition Information SSID Service Set Identifier. Wireless network are represented by their SSID which is the name that shows up when you scan for available wireless networks. A common security feature is to disable the SSID broadcast. Wireless networks can also be secured by using MAC filtering. Wireless networks can also be put onto specific channels ranging from 1 to 14. IEEE = Institute of Electrical and Electronics Engineers SOHO = Small office, Home office. This thread was created by myself from my own knowledge and experience. You may not re-distribute this and it should only be found on mcompute.co.uk