A+ Breakout Ralph D Nyberg Networking

Addressing Physical/Mac Address/Hardware Address 12 digit hex 1st 6 digits Vendor ID Associated with NIC Can be viewed with ipconfig /all

Addressing (cont) Network/Software/Logical/IP Address Required Elements IP Address :192.168.1.100 Subnet Mask :255.255.255.0 Required to reach other networks Default Gateway :192.168.1.250 Required to Resolve Names DNS Server :192.168.20.5 Does not have to be local

Addressing (cont) Role of the Subnet Mask The Subnet Mask defines which portion of the IP address defines the network and which portion defines the host. Computers use binary(base 2) numbering to store values. IP addresses and subnet masks are 32 bits or 4 bytes. For example, a subnet mask of 255.255.255.0 written in binary looks like: 11111111.11111111.11111111.00000000 An on bit (1) in the subnet mask indicates that it is part of the network portion of the address and an off (0) bit indicates that it is part of the host address. Take the following example: IP Address :192.168.1.100 Subnet Mask :255.255.255.0 The network portion of this address is 192.168.1 and the host portion is .100. All hosts on the same subnet must share a common network address and must have a unique host address. By looking at the example you know that all the other hosts on the same subnet will have an address that begins with 192.168.1 and cannot end with 100.

Addressing (cont) CIDR Notation Sometimes CIDR notation is used to represent an IP address. CIDR notation represents the subnet mask by indicating the number of on (1) bits in the mask. For example, the address 192.168.1.100 with a mask of 255.255.255.0 would be written 192.168.1.100/24 . The 24 represents the 3 bytes of on bits (8+8+8). Another example would be, the address 172.16.4.2 with a mask of 255.255.0.0 would be written 172.16.4.2/16 .

Private Address Ranges Addressing (cont) Private Address Ranges   Certain address ranges have been reserved for use on private networks. They are sometimes referred to as non-routable address because internet router will not forward them because they are reserved for private networks. The ranges are as follows: 10.0.0.0 172.16.0.0 – 172.31.0.0 192.168.0.0 -192.168.255.0 It is always best to use these ranges when setting up a private network to avoid conflict with an existing network on the internet. When using these private ranges technology has to be implemented to allow hosts access to the internet (NAT or PROXY).

Addressing (cont) Address Assignment Static Dynamic Manual Dynamic requires a DHCP server   On the exam if you run into a question where a host address is 169.254.x.x that indicates a problem. The 169.254.x.x address range is used by APIPA (Automatic Private IP Addressing). It is an indication that the host is set to receive an address dynamically but was unable to contact the DHCP server. To answer this question you have to consider the address assignment method that is being used in the environment. If the environment uses static addressing then you need to manually assign the host an address. If the environment uses dynamic addressing then the first step is the make another attempt to acquire an address using the commands ipconfig /release and ipconfig /renew .

Bandwidth Bandwidth is a measure of available or consumed data communication resources expressed in bit/s or multiples of it (kbit/s, Mbit/s etc).

Status Indicators NICs have status indicators or link lights that show activity and indicate an active connection. If the exam question indicates that you have inspected the cabling and have link light then they are telling you that the problem is software based and not hardware based. If you do not have link light then the most common causes of this are: cabling (most common) NIC Dead port on Switch/Hub Switch/Hub is off

Other Protocols IPX/SPX was used by older Novell Netware environments. NWLINK is Microsoft’s implementation of IPX/SPX. NETBEUI is a non-routable protocol used on old Microsoft networks. It has not been included with Microsoft operating systems since Windows 2000.

Full Duplex vs Half Duplex Ethernet switching gave rise to another advancement, full-duplex Ethernet. Full-duplex is a data communications term that refers to the ability to send and receive data at the same time.   Legacy Ethernet is half-duplex, meaning information can move in only one direction at a time. In a totally switched network, nodes only communicate with the switch and never directly with each other. Switched networks also employ either twisted pair or fiber optic cabling, both of which use separate conductors for sending and receiving data. In this type of environment, Ethernet stations can forgo the collision detection process and transmit at will, since they are the only potential devices that can access the medium. This allows end stations to transmit to the switch at the same time that the switch transmits to them, achieving a collision-free environment.

UTP UTP is the most common cabling used in modern LANS. PVC vs. Plenum Rated PVC stands for Poly Vinyl Chloride, which is the insulation used around the copper wires. When it burns, it emits a poisonous gas. Plenum Rated, which is a TEFLON (copyright Dupont) or FEP coating burns at a much higher temperature and is not as toxic. When should I use PVC and when should I use Plenum Rated?  Well it depends. PVC cable is about 1/2 to 1/3 the price of Plenum Rated cable. Plenum rated cables is used in air plenum ceilings where the return air is forced through the ceiling, rather than being ducted through air conditioning tubes. You should check with the Building and Safety Department of your City. Different cities have different regulations. In general, Plenum Rated cable must be used in an air plenum ceiling.

UTP (cont) TYPE USE Speed CAT 1 Voice CAT 2 DATA 4 Mb/s CAT 3 Ethernet Fast Ethernet 100 Mb/s CAT 5E Fast/Gig Ethernet 1000 Mb/s @ 350 Mb/s CAT 6 Gig Ethernet 1000 Mb/s

RJ45

RJ11

F-Type

SC Connector

ST Connector

MT-RJ

LAN/WAN LAN WAN Private Public (telco) High Speed Low Speed Single Location Multi Location

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