IS452 Exam2Review

Card Set Information

Author:
tttran1
ID:
243737
Filename:
IS452 Exam2Review
Updated:
2013-10-31 06:51:41
Tags:
is452exam2review
Folders:

Description:
review for exam2 of is452
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user tttran1 on FreezingBlue Flashcards. What would you like to do?


  1. ARP
    • ○Address Resolution Protocol
    • ○ Data traffic is routed using the network addresses
    • ○ Data traffic is forwarded over a physical network using MAC addresses
    • ○ ARP is a method used in TCP/IP suite to map network addresses to MAC addresses
  2. Transmission methods
    • unicast
    • multicast
    • broadcast
    • connection oriented
    • connectionless oriented
  3. Unicast
    § Single packet from source to destination
  4. Multicast
    § Single packet that is sent to a specific subset of nodes
  5. Broadcast
    § Single packet that is sent to all nodes
  6. Connection oriented
    • -must first establish a connection before sending data
    • § Connection Establishment, data transfer, and connection termination
    • § Method used for TCP
  7. Connectionless service
    • - can send the data without the need to establish a connection
    • § Transfer can simply send the data without the added overhead
    • § Method used for UDP
  8. Local Area Network (LAN)
    • ○ A high-speed network that is bounded by a small geographic area
    • □ Tends to encompass one broadcast domain
    • □ Usually restricted to a building or floor
    • □ Operates at the layer 1 and 2 of the OSI model
    • □ Interconnected using a hub or switch
  9. Ethernet
    • ® Most commonly used
    • ® Duplex – full/half
    • ® Speed – 10/100/auto
  10. Data Identification at OSI Layers
    • ○ Segment – Transport layer (Layer 4)
    • ○ Packet – Network Layer (Layer 3)
    • ○ Frame – Data Link Layer (Layer 2)
  11. Switching layers
    • access layer
    • distribution layer
    • core layer
  12. Access Layer
    • ○ This is the bottom layer of the 3 layer network design
    • ○ Users are connected at this layer
    • ○ Collision domains can be limited through VLANs
  13. Distribution Layer
    • ○ Routing (or at the Core Layer)
    • ○ Packet Filtering
    • ○ QOS
  14. Core Layer
    ○ High speed data transfers and reliability
  15. Cisco Switches
    • ○ Cisco switches can be modular in the number of ports they allow or non-modular
    • § Non-Modular come in different sizes but the sizes are fixed and cannot be expanded
  16. Virtual Area LAN Network (VLAN)
    • ○ A LAN not restricted by physical location
    • § Can be developed based on more than physical location
  17. ○ Benefits of VLAN
    • § Performance
    • § Formation of virtual workgroups
    • § Easy Administration
    • § Cost
    • § Security
  18. Dynamic VLANs
    • § Switch ports are joined to a VLAN based on the workstation’s MAC address
    • § Cisco Works 2000 or VLAN Management Policy Server (VMPS) can be used to associate MAC addresses to VLANS
    • § Management is a headache in large networks
  19. Static VLANs
    • § Membership is based on the VLAN that a switch port belongs to
    • □ Every port is configured to be belong to a VLAN
    • § Static VLANs allow for tighter control of resources and user movement
    • § Easy management
    • □ No need to maintain large MAC address tables
  20. CatOS
    • § OS loaded on Switches
    • § Older OS and Cisco is working to move away from CatOS and to IOS
    • □ IOS is used on routers
    • § New equipment shipped comes with IOS
  21. Communication Closets
    • ○ Ethernet has limits of 100 meters
    • § Wiring runs longer than 100 meters could cause service failures
  22. Trunking
    • ○ A method to support multiple VLANs that have members on more than one switch
    • ○ Switches tag each frame so that the receiving switch knows which VLAN the frame belongs to
  23. ○ Two trunking methods
    • § Cisco Inter-Switch Link (ISL)
    • § IEEE 802.1q
  24. ○ Cisco ISL
    • § ISL created before IEEE standardized a trunking protocol
    • § ISL is a Cisco proprietary so it can only be used between Cisco switches
    • § ISL encapsulates each Ethernet frame with an ISL header and trailer
    • □ ISL header is 26 bytes
    • ® VLAN number is encoded in header
    • □ ISL trailer is 4 bytes CRC
  25. ○ 802.1q
    • § Developed in 1998
    • § Actual frame is modified or tagged
    • □ 4 bytes are added to the original Ethernet header
    • ® A field within this header identifies the VLAN number
    • § FCS is recalculated
  26. DTP
    • Dynamic Trunk Protocol (DTP)
    • ○ DTP is the process that takes place to determine whether tow connecting devices can create a trunk connection
    • § Supports auto-negotiations for both ISL and 802.1q
  27. VTP
    • • VLAN Trunking Protocol (VTP)
    • ○ VTP is a Cisco proprietary messaging protocol that occurs between devices on trunk ports
    • § Allows VLAN information to be propagated across your switched network so you have a consistent VLAN configuration
    • § Makes management easy
    • □ Propagates across mixed media
  28. VTP Domain
    □ A management domain is a grouping of switches that will be sharing information about VLANs
  29. VTP Modes
    • □ Server- Responsible for making all VLAN configurations (adds/changes/deletions)
    • □ Client- Accepts VTP messages
    • □ Transparent- Do not participate in management domain but do forward messages
  30. VTP Messages
    • § Summary- Generated every 300 seconds to ensure all switches are in sync; -Contains a revision number
    • § Request- Generated to acquire VLAN information
    • § Subset- Generated in response to a request
  31. VTP Pruning
    • § Allows a switch to make intelligent decisions concerning the forwarding of multicast, broadcast, and unknown destinations across trunk ports
    • § Turned off by default
    • § Switch must be in Server mode
    • § Pruning can be done manually
  32. STP
    • • Spanning Tree Protocol (STP)
    • ○ A protocol developed to prevent loops
    • § Places a port in either blocking or forwarding state
    • □ Ports that are in forwarding state can send and receive frames
    • § Traffic has to take longer paths
  33. How does STP Work
    • ○ STP selects a root bridge
    • § All interfaces on the root bridge in forwarding state
    • ○ All other bridges select a port that has the least administrative cost between itself and the root bridge.
    • § This port is called the root port
    • ○ Every port is configured to be belong to a VLAN
    • ○ All switches send out bridge protocol data units (BPDU) with the following information
    • § Root bridge’s ID ID (MAC address+priority)
    • □ Default priority is 32768
    • § Cost to reach the root
    • § Bridge ID of the sender
    • ○ Bridge with the lowest ID becomes the root bridge
  34. Hello Time
    • § How long a root waits before sending periodic hello BPDUs.
    • □ Default is 2 seconds
  35. MaxAge
    • § How long a bridge should wait, after beginning to not hear hellos, before trying to change the STP topology
    • □ Default is 20 seconds
  36. Forward Delay
    § Delay that affects the time involved when an interface changes from blocking state to forwarding state
  37. “Portfast” Command
    § When configured it skips the STP port states and places the port into forwarding state immediately
  38. ARP
    • ARP (Address Resolution Protocol)
    • 1. Host A want to send data to host B
    • 2. Host A checks to see if it has the ARP entry for Host B - NO.
    • 3. • Host A places the original packet in buffer
    • • Host A creates the ARP Broadcast and sends it
    • 4. • Host B now processes the ARP request
    • ○ Host B first saves the MAC address and IP for Host A in its own ARP table
    • 5. Host B now can respond to the ARP request
    • 6. • Host A receives the ARP reply and can now complete the original packet
    • ○ Host A will save the MAC and IP for Host B in its ARP Table
    • 7. Host A now builds the packet with Layer 3 and 2 information to transmit
  39. Switch MAC-Address Table
    • • MAC-Address Table
    • ○ When this request is sent, the switch saves the MAC Address for Host A and assigns it to Port 1
    • ○ When this reply is sent, the switch saves the MAC address for Host B and assigns it to Port 2
  40. Category 5e copper
    • -Cheap and Ubiquitous
    • ○ Successor to Category 5, which itself is a successor to Category 3
    • ○ Speeds up to 1 Gbps
    • ○ Requires 2 pair for 10/100, 4 pair for 1Gb
    • ○ Maximum segment length of 100m
    • ○ Also used for voice communications in newer building installations
    • ○ Power over Ethernet is possible
    • ○ Small cable diameter, easy to field terminate
  41. Category 6a cable: copper
    • § Speeds up to 10Gbps
    • § Requires 4 pairs
    • § Maximum segment length of 100m
    • § Much tighter controls on installation standards make field terminations significantly harder
    • § More attention is paid to eliminate NEXT (near-end crosstalk), ANEXT (alien near-end crosstalk) and PSNEXT (power-sum near-end crosstalk)
  42. Category 7a cable (proposed): copper
    • § Speeds up to 100Gbps at 15 meters, potentially 100 meters as electronics improve
    • § Bandwidth up to 1GHz means potential for broadband cable television
    • § Individually shielded pairs, as well as shielded cable
  43. Single Mode Fiber (SMF): Fiber Optics
    • Ride the Light
    • ○ Speeds of 10, 40, 100Gbps and higher
    • ○ Distances of hundreds of miles or more
    • ○ Use highly tuned, single-mode laser optics
    • ○ Smaller core size greatly reduces modal dispersion
    • ○ Typically used for connections between buildings, and even further distances
  44. Multi Mode Fiber (MMF): Fiber Optics
    • Ride the Light
    • ○ Speeds up to 10Gbps
    • ○ Distances up to 2km
    • ○ Can be used with LEDs instead of lasers, making optics much cheaper
    • ○ Larger core size enhances modal dispersion; the signal can become spread in time
    • ○ Typically used for connections within a building
  45. IEEE 802.11
    • Wireless
    • The Standard We All Know and Love
  46. 802.11b
    • § Introduced in 1999
    • § Bit rates of 1-11 Mbps
    • § 11 20MHz channels in the 2.4GHz band
    • § Three non-overlapping channels (1, 6, 11)
    • § Lower frequency means greater range, can traverse solid objects easier
    • § Interference issues (microwave ovens, Bluetooth devices, wireless keyboards/mice)
  47. 802.11a
    • § Introduced in 1999
    • § Bit rates of 6-54 Mbps
    • § 21 20MHz channels in the 5GHz band
    • § 21 non-overlapping channels
    • § Higher frequency is more susceptible to absorption by surrounding objects
    • § Fewer interference issues
  48. 802.11g
    • § Introduced in 2003
    • § Bit rates of 6-54 Mbps
    • § 11 20MHz channels in the 2.4GHz band
    • § 3 non-overlapping channels
    • § Same strengths and weaknesses as 802.11b
    • § Cheaper manufacturing costs make this standard a commodity
  49. 802.11n
    • § Drafted in 2007, ratified 2009
    • § Bit rates of 300Mbps and higher with channel bonding
    • § 3 20MHz channels in the 2.4GHz band, 21 20MHz channels in the 5GHz band
    • § 24 non-overlapping 20MHz channels
    • § MIMO (multiple in-multiple out) uses multiple antennas for higher bandwidth and more recently beamforming
    • § Multiple antennas cost more, and many manufacturers only implement the 2.4GHz standard, keeping the same limitations as 802.11b and 802.11g.
  50. 802.11ac
    • § Still in draft status, anticipated ratification in 2014
    • § Single stream bit rates of up to 866Mbps
    • § Up to 8 spatial streams instead of 4 in 802.11n
    • § 3 20MHz channels in the 2.4GHz band, 21 20MHz channels in the 5GHz band
    • § 24 non-overlapping 20MHz channels
    • § MIMO (multiple in-multiple out) uses multiple antennas for higher bandwidth
    • § Uses more dense 256-QAM modulation, over 64-QAM used in 802.11n
    • § Gigabit wireless to multiple users possible
  51. Microwave: Wireless Methods
    • § Very high frequencies, very high potential bandwidth
    • § Expensive to deploy, frequency licensing may be an issue
    • § Limited to point-to-point links
    • § Links can be dozens of miles apart
  52. Free-space optical wireless: Wireless Methods
    • § Uses lasers to transmit data, very high (up to 10Gb) bandwidth
    • § Expensive to deploy, costly equipment
    • § Limited to point-to-point links, can be affected by weather
    • § Links can be miles apart
  53. Infrared: Wireless Methods
    • § Also uses light to transmit data, but bandwidth is not as high
    • § Cheaper to deploy
    • § Limited to point-to-point links
    • § Links have limited distance
  54. Cellular: Wireless Methods
    • § HSPA+ (most commonly used by AT&T and T-Mobile)
    • □ Theoretical throughput capacity of 672 Mbps
    • § LTE (most commonly used by Verizon, and now by Sprint Nextel and AT&T)
    • □ Theoretical throughput capacity (with LTE-Advanced update) of 1Gbps
  55. Bluetooth: Wireless Methods
    • § Primarily used to create (relatively) low data speed personal area networks
    • § Also used for wireless keyboards, mice, headsets
  56. 802.16
    • -Other IEEE Standards; What’s to Come
    • ○ Drafted in 2001, ratified in 2004, currently in use as 802.16-2009
    • ○ Also known as WiMAX or WirelessMAN, it is meant to operate at microwave frequencies (10-63GHz)
    • ○ Speeds up to 128Mbps for mobile and 1Gbps for fixed stations but at a much greater range, up to 50 miles
  57. 802.20
    • -Other IEEE Standards; What’s to Come
    • ○ Published in 2008
    • ○ Also known as MBWA (mobile broadband wireless access), it is meant to provide up to 80Mbps access to clients moving up to 250km/h
    • ○ Operates in licensed frequencies below 3.5GHz
  58. 802.22
    • -Other IEEE Standards; What’s to Come
    • ○ Published in July, 2011
    • ○ Also known as WRAN (wireless regional area network), aims to use white spaces in current television broadcast spectrum
    • ○ Can be used to help get access to people still too far from traditional broadband technologies (DSL, cable, etc.)

What would you like to do?

Home > Flashcards > Print Preview