Adding LAN Ports

I have an old Asus RT-N15 Router sitting around doing nothing and was thinking of setting it up in the living room to add more LAN ports and to improve wifi reception as a 2nd AP (Access Point) SmallNetBuilder is a Good site and has good links for subnetting a 2nd router. http://www.smallnetbuilder.com/lanwan/lanwan-basics/30740-how-to-use-a-router-to-add-network-ports?start=1 It turns out in my Administration Tab I can change it from Home Gateway to Access Point. In Access Point mode, four LAN ports in the RT-N15 and other wireless devices are set up in the same local area network. The WAN related functions are not supported in this mode. In this mode, NAT is disabled and four LAN ports in the RT-N15 and other wireless devices are bridged together. In the Manual it mentions that even the WAN port will be modified to work like a LAN port. This should prevent the need for another subnet. I think all I will need is a static IP so I can always remote into this device.

MAC ADDRESS

MAC (Media Access Control) aka Hardware Address is burned into every ethernet NIC.
48 bits (6 bytes in Hex).

MAC Fields

Bit Range	Field Name	Decimal	Hex	Info
47 (1 Bit)	Individual/Group (Broadcast)	0		1 Indicates this MAC Address is a Broadcast or Multicast Address 0 Means this is a Device Address.
46 (1 Bit)	Global/Local OUI	0		1 Indicates this is a locally governed OUI Address 0 Globally Administered IEEE OUI Address.
45-24 (22 Bits)	OUI (Organizationlly Unique Identifier)	0	0	Company ID. Assigned by IEEE.
23-0 (24 Bits)	Vendor/Maufacturer Assigned ID	0	0	Usually NIC SN.

Link to lookup OUI at IEEE
http://standards.ieee.org/develop/regauth/oui/public.html

Ethernet Cable

Unshielded Twisted Pair (UTP). The more twists the less cross talk.
In 56A Pins 1 and 2 have green in them.
In 56B Pins 1 and 2 have Orange in them.
If the colors on one side of the cable are in different order than other side, then we have a crossover cable as apposed to straight thru cable. My home routers all have Smart Sense technology so a crossover cable is not necessary to connect WAN ports. Crossover cables are usually used to connect switches/routers or workstations directly without the use of a router.

OSI Layers

Open Systems Interconnection.
Links
http://en.wikipedia.org/wiki/OSI_model

Please Do Not Throw Sausage Pizza Away.

1. Physical
2. Data
3. Network
4. Transport
5. Session
6. Presentation
7. Application

1. Physical - Bits
2. Data Link - Frames
3. Network - Packets
4. Transport - Segments

Physical

Physical Topology. Moves Bits between devices. NIC Card. Hub. Repeaters. Wires.

Data Link

Logical Topology. Framing. Error Detection, Notification (NOT Correction). Flow Control. Delivery on LAN using MAC, Physical Addresses. Switches and Bridges. Switches Break up Collision Domains. Data Frames have source and destination MAC Address in header. LLC (Logical Link Control) Header. MAC (Media Access Control) Header.

Network

Routed Protocols IP (Header) and IPV6 transport Data Packets through an internetwork (devices that aren't locally attached). Logical Addressing. Routing Protocols update neighboring routers with Route Update Packets. Examples are RIP Routing Information Protocol, EIGRP Enhanced Interior Gateway Routing Protocol, and OSPF Open Shortest Path First. Routers break up Broadcast Domains, will not forward broadcast or Multicast packets. Routing Table Holds Network Address, Interface, Metric

Transport

TCP, UDP (header). Reliable or Unreliable Delivery. Error Correction before re-transmit. Connection Oriented Communication. Virtual Circuit. SYN, SYN/ACK, ACK. Three way handshake. Flow Control. Receiver governs amt of data sent by sender by sending ack for each segment. Segments are ordered - delivered in the order they are transmitted. Window is the # of segments that can be sent without waiting for a Flow Control ack. Positive acknowledgement with retransmission.

Session

simplex, half duplex,full duplex.

Presentation

Translation. Compression. Encryption. EBCDIC to ASCII

Application

FTP, HTTP, SMTP, SNMP, Telnet, DNS, DHCP.

IP Addresses

The Host ID of 0 is always reserved to represent the network itself. The Host ID of 255 is reserved for broadcasts to all hosts on network. The iana Has a list of all Class A Blocks by company. 127.0.0.0-127.255.255.255 is reserved for Loopback (localhost).

Classful network

Class	1st 4 Bits	Network ID Range xyz for Host Octets	Network Bit Length	# of Networks	# of Hosts	Host ID Range wxy for Network Octets
A	0-------	001-126.x.y.z	8	126	16,777,214	w.1-254.1-254.1-254
B	10------	128-191.1-254.y.z	16	16,384	65,534	w.x.1-254.1-254
C	110-----	192-223.1-254.1-254.z	24	2,097,152	254	w.x.y.1-254
D	1110----	224-239.x.y.z			wiki
E	1111----	240-254.x.y.z

Subnetting

Supply the Subnet Mask OR CIDR (Classless InterDomain Routing) # and IP Address.

Network ID
Host ID
Hosts Allowed
IP Block Range Min
IP Block Range Max
Class
Default Subnet

Private Address Ranges

Use the following Private Address Ranges for use behined a Firewall, not on the public internet. They cannot be used on the public internet.

CIDR	Subnet Mask	Network ID Range xyz for Host Octets	Host ID Range y for Network Octets	IP Range
10.0.0.0/8	255.0.0.0	10.x.y.z	10.1-254.1-254.1-254	10.1.1.1 10.255.255.255
172.16.0.0/12	255.255.240.0	172.16.y.z	172.16.1-254.1-254	172.16.1.1 172.31.255.255
192.168.0.0/16	255.255.0.0	192.168.1-254.z	192.168.y.1-254	192.168.1.1 192.168.255.255