Introduction to Utp

3) a) Physical layer b) 100base-TX shows that it is a baseband transmition. It has 100 Mbps of speed which is usually the speed of the NIC and switch port and the T shows UTP wiring used c) Baseband injects the signal into each transmition medium. Broadband transmition sender transmits signal in radio channels d) Baseband transmition is cheaper than broadband e) This implies that NIC’s and switches can do autosensing. So if 100BASE-TX detects 10BASE-FX at the other end it can slow down its speed to 10 Mbps f) Slowing down of the speed of the physical layer to accommodate to the speed of a detected switch or NIC g)100 Mbps Ethernet standard is Ethernet standard h) 100BASE-TX i)gigabit Ethernet 1000BASE-x j)10 GBASE-x and 40 GBASE-x

4) a) When 2 or more trunk lines connect a single pair of switches using the 802.3 standard. This is used to increase Ethernet transmition capacity by less than 10. b) Because it is less expensive and usually increments by a smaller factor of two or three instead of 10. c) Cost wise it may be better to implement a 10-fold increase in capacity instead of link aggregation.

7) a) synchronizes receivers clock to senders clock. b) Ethernet address are at the MAC layer so they are called MAC address. They are also called physical address because physical devices implement Ethernet at the physical, MAC and LLC layer c) Divided the 48 bits in to 12-4 bit units called nibbles, convert each nibble in to hexadecimal symbol, then write the symbol in to 6 pairs with a dash between each pair. d) the data filed e)LLC sub header and the encapsulated packet. f) describe the type of the packet contained g)IP packet h)1500 octets i)The sender adds the PAD field j) No k)6 octets so that the total data field is 46 octets l) 0, since the data filed is more than 46 octets long no PAD field is needed. m) It permits error detection by recalculating the binary number in the field if it’s incorrect n) The receiver discards the frame o) C2

8) No individual switches work the same way however in multiswitch LAN’s the switch may be forwarding the frame to another switch instead of the destination station without knowing they merely send the frame out the indicated port but do not know if it is going to the destination host or to another switch. b) Switch 2 will do the same thing it will read the address through the switching table and send it out the indicated port without knowing if it will be going to the destination host or to another switch. According to the example switch 2 will send through port 7 which has the address of the destination host however on the way the frame is forwarded to another switch, switch 3, which switch 2 is unaware of. c) Switch 3 reads the destination host address on the frame which is out port 6 and sends it through this port which is directly transmitted to the destination host.

Design questions

1) 1000BASE- T

2) 10GABSE-SR/SW or to minimize cost we can use a 1000BASE-SX and use link aggregation between the two switches

Chapter 5

14a) wireless access point, wireless station (wireless NIC) and the wired LAN which includes the server it wishes to reach.

b) Because the servers that mobile client devices need, Internet access routers are usually on the wired LAN. c) Bridge d) Because it is dealing with 2 different types of LAN and the frames cannot travel on each type of LAN unless it is put in the right frame e)when the station is handed of to another access point because the signal becomes too weak from the station to reach the access point f) In WLAN hands-off and roaming mean the same thing .The ability to use hands-off is roaming. g) Because all the access points and the wireless stations it serves transmits and receives in a single channel so collision can occur distorting the signals being transmitted.

15) a)media access control ensure that the stations and the access points do not send in the same time b)both

16) a) CSMA/CA+ACK stands for carrier sense multiple access collision avoidance . The sender listens for traffic if there is no it sends the information. If there is no traffic and a critical time has been exceeded it can transmit otherwise it waits a random amount of time then it can send. The receiver then sends an ACK frame to the sender to ensure that the information has been received. b) It is reliable because the receiver sends and acknowledgement frame that the information has reached and if the sender does not receive that frame the message is sent again. c) It is inefficient because sending ACK is time consuming in addition, having to wait before