Networking/Ethernet Training Guy Walker Training and A&E Manager

1. Networking/Ethernet Training Guy Walker Training and A&E Manager

2. “Review” • IP addressing scheme (class A, B, etc) • MAC address vs. IP address • TCP vs UDP • OSI layers • Topologies • Why is it hot? • What solutions do you use? • What issues are you seeing?

3. Basic Network Components • Switches, hubs • Cabling • Edge devices • Protocols • Language of packets • Relates to network • Relates to devices on network 00101101011100101001010101010100101101110000101 00101101011100101001010101010100101101110000101

4. Edge Device Edge Device 100Mbps Network Parking Lot Edge Switch Wireless Bridge Core Switch Gateway Bridge Gigabit Network DVR Remote Office Building Corporate Office Building WAN Remote Client

5. Security Architecture Example INTERCOM DVR CARD ACCESS MATRIX SWITCH VIDEO IP CODEC DATA OVER IP VOIP VOIP

6. Types of Networks • LAN – Local Area Network • A network covering a small physical area, like a home, office, or small group of buildings, such as a school, or an airport. • MAN – Metro Area Network • A MAN is a network larger than a LAN, ranging from several blocks of buildings to entire cities. A MAN might be owned and operated by a single organization, but it usually will be used by many individuals and organizations. MANs might also be owned and operated as public utilities. • WAN – Wide Area Network • A network that covers a broad area (i.e., any network whose communications links cross metropolitan, regional, or national boundaries). Less formally, a WAN is a network that uses routers and public communications links. Source: IEEE Standards

7. Types of Messages • Unicast • A one-to-one communication link. Packets are sent from one IP address to another IP address. • Broadcast • A one-to-everyone communication link. Packets are sent from one IP address to all ports and IP addresses on the network. • Multicast • A dynamic, one-to-many communication link. Packets are sent from one IP address to any other IP addresses that request the packets. Since this a dynamic relationship, devices can “subscribe” and “un-subscribe” at will. • IGMP – Internet Group Multicasting Protocol

8. Multicasting Example 001011010111001010010101010101001011011 0010110101110010100101010101010010110111 0010110101110010100101010101010010110110010101000110101 001011 001011 001011 001011 Command Center Remote Client

9. Application 7 Mostly software 6 Presentation Session 5 4 Transport 3 Network Mostly hardware 2 Data link 1 Physical OSI Model Layer 3 (Router) Layer 2 (Switch) Layer 1 (Hub and cables) The Open Systems Interconnection model defines seven functional layers of the overall system. A layer is a group of conceptually similar functions that provide services to the layer above it and receives service from the layer below it. Source: Wikimedia Commons

10. Application 7 Mostly software 6 Presentation Session 5 4 Transport 3 Network Mostly hardware 2 Data link 1 Physical OSI Model - Examples HTTP, Telnet MPEG, SSL Half/Full Duplex TCP, UDP IP, IGMP 802.3 (Ethernet), VLAN, PPP RS-232, POTS, 802.11 (wireless), 10Base-T Source: Wikimedia Commons

11. Ethernet • Ethernet is a family of frame-based computer networking technologies for local area networks (LANs). • Packets • It defines a number of wiring and signaling standards for the Physical Layer of the OSI networking model, through means of network access at the MAC/Data Link Layer, and a common addressing format. • Layer 1 and 2 • Ethernet is standardized as IEEE 802.3. This includes versions for twisted pair cabling, fiber optics and wireless. • 10Base-T • 100Base-T (Fast Ethernet) • 1000Base-T (Gigabit) • 100Base-FX, etc. (fiber-based)

12. Ethernet Packet Source: Wikimedia Commons

13. Connectors and Cabling RJ-45 SC LC RJ45 – morecorrectly called the 8 Position 8 Contact (8P8C) connector. SC – fiberopticcableconnector LC – fiberopticcableconnector

14. Connectors and Cabling • Category 5 UTP • Four twisted pairs in a single cable jacket. • Up to 100Mbps • Typically has three twists per inch of each twisted pair of 24 gauge copper. • NO Power Over Ethernet (POE). • Category 5e UTP • Four twisted pairs in a single cable jacket, but more twists per inch to avoid crosstalk. • Up to 1000Mbps. • Category 6 UTP or STP • Four twisted pairs. • Up to 1000Mbps • Category 7 STP • Four individually shielded pairs inside an overall shield. • Up to 10Gig

15. Manufacturer Hardware MAC Address The Media Access Control layer of the OSI stack. This is the lowest layer (Layer 1) and makes for an easier and more simplified packet transfer. A MAC address is a 48-bit address defined by the manufacturer and the hardware. It is a hard-coded, unique address that is burned onto the device during manufacturing. The first three bytes will define the manufacturer and the last three bytes define the device. 00-2A-9Z-3C-78-05

16. MAC Address MAC Addresses essentially provide an unchanging, unique network identifier for a device. This also adds another layer of security that may be utilized within the network. Switches convert IP addresses to MAC addresses to deliver packets.

17. Internet Protocol TCP/IP The Internet Protocol Suite (commonly TCP/IP) is the set of communications protocols used for the Internet and other similar networks. It is named from two of the most important protocols in it: theTransmission Control Protocol (TCP) and the Internet Protocol (IP), which were the first two networking protocols defined in this standard.

18. Internet Protocol • TCP - is responsible for verifying the correct delivery of data from client to client, and to trigger retransmission until the data is correctly and completely received. • IP - is responsible for moving packets of data from node to node. IP forwards each packet based on the IP address. The IP scheme operates through “gateway” machines that allows data to move from department to organization to region and then around the world. • Socket - is an end-point of a bidirectional process-to-process communication flow across an IP based network. A socket is an interface between an application process and the TCP/IP protocol stack provided by the operating system. Source: Wikimedia Commons

19. IP Addressing 126.15.101.10 • IP Version 4 (current) • 32 bit binary code • 4 sections of 8 bits each • Network ID, Host ID • IP Addressing rules: • The Network ID cannot start with a ZERO • The Host ID cannot end with a ZERO • No two systems, on the same network, can have the same Host ID • No two systems on one network can have the same IP Address. • An octet’s value will never exceed 255 • IP Version 6 (future) • 128 bit binary code • 3ffe:1900:4545:3:200:f8ff:fe21:67cf • Backwards compatible

20. Network ID Host ID IP Addressing Class A • n = network h = host • nnnnnnnn.hhhhhhhh.hhhhhhhh.hhhhhhhh • NOTES: • The 127.1.1.1 address is reserved for MS Loopback. • Over 16 million possible HOSTS First Octet range (1-127)

21. Network ID Host ID IP Addressing Class B • n = network h = host • nnnnnnnn.nnnnnnnn.hhhhhhhh.hhhhhhhh • NOTES: • Over 65,000 possible HOSTS First Octet range (128-191)

22. Network ID Host ID IP Addressing Class C • n = network h = host • nnnnnnnn.nnnnnnnn.nnnnnnnn.hhhhhhhh • NOTES: • Only 254 possible HOSTS First Octet range (192-223)

23. IP Addressing ClassD Multicast 224.0.0.0 to 239.255.255.255 Class E Experimental 240.0.0.0 to 254.255.255.255

24. IP Addressing • Private Addresses • Three ranges assigned by Internet Assigned Numbers Authority (IANA): • Computers not connected to the Internet do not need to have globally unique IP addresses. These addresses are not routed on the Internet, and thus do not need to be coordinated with an IP address registry. 10.0.0.0 To To To 10.255.255.255 172.16.0.0 172.31.255.255 192.168.0.0 192.168.255.255

25. IP Addressing • Multicasting • IGMP – Internet Group Management Protocol • Reserved IP Addresses: • Any Ethernet packet with an IP destination within this range will be treated as a Multicast stream by network switches/routers that support IGMP. • A multicast address is associated with a group of interested receivers. The sender sends a packet to the multicast address, and the intermediary routers take care of making copies and sending them to all receivers that have registered their interest in data from that sender • This range was formerly called "Class D." 224.0.0.0 To 239.255.255.255

26. Multicasting Example 001011010111001010010101010101001011011 0010110101110010100101010101010010110111 0010110101110010100101010101010010110110010101000110101 001011 001011 001011 001011 Command Center Remote Client

27. IP Scheme WAN switches Workgroup switches Workstations, cameras, access Source: Microsoft TechNet

28. IP Addressing Subnet Masking A way of further segregating HOSTS in a network. Subnetting allows the network to be logically divided regardless of the physical layout of a network, since it is possible to divide a physical network into several subnets by configuring different host computers to use different routers Class C– 192.168.151.1 Class C – 255.255.255.0 masking Class A – 255.0.0.0 Class B – 255.255.0.0 Class C – 255.255.255.0

29. VLAN Virtual Local Area Network 802.1Q A configuration scenario where hosts are separated into groups to segment traffic on the network. VLANs are created to provide the segmentation services traditionally provided by routers in LAN configurations. VLANs address issues such as scalability, security, and network management. Switches may not bridge IP traffic between VLANs as it would violate the integrity of the VLAN broadcast domain. Virtual LANs are essentially Layer 2 constructs, compared with IP subnets which are Layer 3 constructs. Source: Wikimedia Commons

30. VLAN Emergency Phone (VLAN 1) Video(VLAN 2) Card Access(VLAN 3) Operations Center (Operation Center belongs to all 3 VLANs)

31. VLAN IP Codecs Port 1 VLAN 1 Port 2 VLAN 2 Port 5 VLAN 3 Emergency Phone Card Access Video

32. Protocols • Network protocols are a convention or standard that controls or enables the connection, communication, and data transfer between two computing endpoints. • Most protocols specify one or more of the following behaviors: • Detection of the underlying physical connection (wired or wireless), or the existence of the other endpoint or node • Handshaking • Negotiation of various connection characteristics • How to start and end a message • How to format a message • What to do with corrupted or improperly formatted messages • Termination of the session or connection

33. Protocols • SNMP • Simple Network Management Protocol • SNMP is used to monitor network-attached devices for conditions that warrant administrative attention. It consists of a set of standards for network management, including an Application Layer protocol, a database schema, and a set of data objects. • MIB – Mgmt Information Base – a type of database that describes the condition of a network device. • MIB Library • Agent • TRAP • RMON • Remote MONitoring • A MIB that uses SNMP to communicate • “Flow based” monitoring versus SNMP’s “device based” monitoring • A little easier to implement RFC 3411 — An Architecture for Describing Simple Network Management Protocol (SNMP) Management Frameworks

34. Protocols • Routing • A Layer 3 protocol • Routing is utilized to effectively manage data packets on the network. The Router does this by the use of a preconfigured “Routing Table”. • This can be accomplished a few different ways based on the level of routing allowed by the Router. • The three common routing tools are as follows: • IP Address • MAC Address • System Name

35. Protocols RIP – Routing Information Protocol - an older interior gateway protocol (IGP) using the distance-vector routing algorithm. Considered outdated. IS-IS– Intermediate System to Intermediate System: is a link-based routing protocol, meaning that it operates by flooding network topology information throughout the routers. Each router will then independently build a picture of the network's topology. Likewise, packets are forwarded based on the best path through the network to the destination address.

36. Protocols • OSPF– Open Shortest Path First - is another dynamic routing protocol for use in IP networks. Specifically, it is a link-state routing protocol and falls into the group of interior gateway protocols, operating within an autonomous system. • TCP versus UDP • TCP has error correction • UDP is “fire and forget” • Implications for video streaming

37. Spanning Tree Protocol IEEE 802.1d Defined as where two bridges are used to interconnect the same two computer network segments, spanning tree is a protocol that allows the bridges to exchange information so that only one of them will handle a given message/packet that is being sent between two computers within the network. The spanning tree protocol prevents the condition known as a bridge loop. Also provides redundancy capability when switches are connected in a ring topology. 30 to 50 second response.

38. Rapid Spanning Tree Protocol IEEE 802.1w Same purpose as STP, but with faster results – and it’s backwards compatible to STP. Less than 1 second response.

39. Rapid Spanning Tree Protocol

40. RSTP and IGMP

41. RSTP and IGMP

42. Protocols • QoS • Quality of Service is the ability to provide different priority to different applications, users, or data flows, or to guarantee a certain level of performance to a data flow. • CoS • Class of Service is a field within a layer two Ethernet frame header. It specifies a priority value of between 0 (signifying best-effort) and 7 (signifying priority real-time data) that can be used by Quality of Service disciplines to differentiate traffic. • DHCP(Server) • Dynamic Host Configuration Protocol is used by networked devices (hosts) to obtain the parameters necessary for operation in an IP network. • NTP • Network Time Protocol is a protocol for distributing the Coordinated Universal Time (UTC) to computer systems across a network.

43. Real Problems • Dropped Packets • Routers or switches might fail to deliver (drop) some packets. This is normal for most networks and is not a concern unless it happens in large amounts. • Lost Packets • This is not good. This means packets were dropped but can’t be retransmitted. • Delay • It might take a long time for a packet to reach its destination because it gets held up in long queues, or takes a less direct route to avoid congestion. In some cases, excessive delay can render an application, such as video, unusable. • Jitter • Packets from the source will reach the destination with different delays. This can seriously affect the quality of streaming audio and/or video. (UDP can solve this)

44. Problems, Really? • Bad IP Scheme • Can cause lots of problems – like edge devices dropping off the network. • Edge Devices • These need to be configured properly, especially video. Are reduced frame rates being used? Is it your recorder? etc • Multicast Support • All network devices need to support IGMP on large or busy systems. • Bandwidth • Are you exceeding limits? What is an appropriate limit? • Standard vs. Custom Protocols • Many big switch manufacturers customize standard protocols.

45. Wireless • IEEE 802.11 is a set of standards for wireless local area networks (WLAN), in the 5 GHz and 2.4 GHz public spectrum bands (unlicensed). • 802.11b and 802.11g – use 2.4GHz ISM band and gets up to 54Mbps over up to 38 meters. • 802.11n – not a standard yet, but up to 600Mbps by utilizing MIMO. • Point-to-Point • Point-to-Multipoint • Mesh

46. Wireless Topologies Point-to-Point

47. Wireless Topologies Point-to-Multipoint

48. Wireless Topologies Mesh

49. Wireless • Pros • Less expensive than running cable • Indoor and outdoor • Flexible • Cons • Unreliable • Interference • Limitations

50. Power Over Ethernet • PoE IEEE 802.3af • DC power over Ethernet cable - CAT 5e or higher • Supplies 48V at 350 mA max • 13 Watts max • PSE – Power Source Equip. • PD – Powered Device • Midspan Hub • Endspan Hub • Can you put a non-PoE • Device into a PoE switch? • 25k Ohm resistor • 802.3at standard coming – supplies more power