Networking concepts
- 1. Ethernet Technology and its Evolution
- 2. Ethernet Technologies • Ethernet Network Elements • Ethernet Network Topologies and Structures • The IEEE 802.3 Logical Relationship to the OSI Reference Model • Benefits of Ethernet Evolution of Ethernet • Ethernet Speed Developments • Gigabit Ethernet • 40 GE Transmission • 100 GE Transmission • 400 GE Transmission Overview
- 3. Ethernet Network Elements The Ethernet IEEE 802.3 LAN can be considered to consist of two main elements: 1. Interconnecting media 2. Network nodes There are some interconnecting medias: • Coaxial Cables • Twisted Pair Cables • Fiber optic cable The network nodes we can divide into two major classes: • Data Terminal Equipment (DTE) • Data Communication Equipment (DCE)
- 4. Ethernet Network Elements cont.. Interconnecting medias Network nodes
- 5. Ethernet Network Topologies and Structures There are several network topologies that can be used for Ethernet communications • Point to point • Coaxial bus Topology • Star network Point to point
- 6. Ethernet Network Topologies and Structures cont.. Coaxial bus Topology
- 7. Star network This type of Ethernet network has been the dominant topology since the early 1990s. Ethernet Network Topologies and Structures cont..
- 8. The IEEE 802.3 Logical Relationship to the OSI Reference Model Ethernet’s Logical Relationship to the OSI Reference Model
- 9. MAC and Physical Layer Compatibility Requirements for Basic Data Communication The IEEE 802.3 Logical Relationship to the OSI Reference Model
- 10. Benefits of Ethernet Cost efficiencies Unprecedented scalability and flexibility Protocol neutrality Ease of use Reliability and general availability/ubiquity
- 11. Ethernet Speed Developments Gigabit Ethernet • 40 GE Transmission • 100 GE Transmission • 400 GE Transmission
- 12. Gigabit Ethernet The Gigabit Ethernet standard supports a theoretical maximum data rate of 1gigabit per second (Gbps)(1000 Mbps). Gigabit Ethernet is 100 times faster than regular 10Mbps Ethernet and 10 times faster than 100Mbps Fast Ethernet.
- 13. Advantages Roughly 100 times faster than the regular Mbps Ethernet. Elimination of bottlenecks within the Internet service. Power to transfer large amounts of data across a network quickly. Low cost of acquisition and ownership Seamless integrations with Ethernet and Fast Ethernet-installed base. Gigabit Ethernet cont..
- 14. 40 GE Transmission Multimode ribbon fiber • Used for distances of 100 m on OM3 and 150 m on OM4 MMF • Data is sent using multiple 850 nm lasers transmitting over multiple parallel fibers • MPO cables provide multiple separate transmit and receive strands of multimode fiber in a ribbon cable assembly Single-mode duplex fiber • Used for distances of 2 km, 10 km and 40 km on standard duplex SMF • 40 Gb/s serial transmit over one strand of fiber and receive over the other strand of fiber is used for 40GBASE-FR
- 15. 100 GE Transmission Multimode ribbon fiber • Used for distances of 100 m on OM3 and 150 m on OM4 MMF • Data is sent using multiple 850 nm lasers transmitting over multiple parallel fibers • MPO cables provide multiple separate transmit and receive strands of multimode fiber in a ribbon cable assembly Single-mode duplex fiber • Used for distances of 2 km, 10 km and 40 km on standard duplex SMF • WDM component in the pluggable module multiplexes all transmit lanes over one strand of fiber and all receive lanes over the other strand of fiber
- 16. 400 GE Call for Interest (CFI) was presented at the March 2013 IEEE Plenary and approved to be an official IEEE Study Group Reach objectives adopted by Study Group at the November 2013 IEEE Plenary • 100 m MMF • 500 m SMF • 2 km SMF • 10 km SMF 400 GE standard expected in 2016+ 400 GE Transmission
- 17. 400 GE pluggable module evolution estimates each module increases density, while reducing cost and power
- 20. Wireless Networking Technologies Types of wireless networks, Wireless Personal Area Networks(WPANs) Wireless Local Area Networks(WLANs) Wireless mesh network Wireless Metropolitan Area Networks(WMANs) Wireless Wide Area Networks(WWANs) Cellular network Global Area Network(GAN) Space network
- 21. Wireless Personal Area Networks(WPANs) low-range wireless network, generally cover a range of less than 10 meters (about 30 feet) Using technologies • Bluetooth • Infrared • ZigBee generally used for linking peripheral devices • Printers • Cellphones • Home applications Connect personal assistant(PDA) to a computer, or just two nearby computers, without using a hard-wired connection.
- 22. WPANs cont.. Bluetooth • Invented by telecom vendor Ericsson in 1994 • Exchange data using short- wavelength UHF radio waves in the ISM band from 2.4 to 2.485 GHz. • Bluetooth was standardized as IEEE 802.15.1 • Cover short distances, typically up to 30 feet(10 meters). • Devices generally communicate at less than 1 Mbps Infrared • Electromagnetic radiation with longer wavelengths than those of visible light. • Extending from the nominal red edge of the visible spectrum at 700 nanometers (frequency 430 THz) to 1 mm. • Exist in networks with 3 different forms IrDA-SIR (slow speed) infrared supporting data rates up to 115 Kbps IrDA-MIR (medium speed) infrared supporting data rates up to 1.15 Mbps IrDA-FIR (fast speed) infrared supporting data rates up to 4 Mbps
- 23. WPANs cont.. ZigBee • ZigBee is based on an IEEE 802.15 standard • ZigBee is used in applications that require only a low data rate, long battery life, and secure networking • Defined rate of 250kbps • ZigBee networks are secured by 128 bit symmetric encryption keys • Transmission distances range from 10 to 100 meters line- of-sight, depending on power output and environmental characteristics
- 24. Wireless Local Area Networks(WLANs) Cover larger area than WPANs Modern WLANs are based on IEEE 802.11 standards Interconnects computers within a limited area such as a home, school, computer laboratory, or office building, using wi-fi technology. Wireless LANs have become popular in the home due to ease of installation. Also referred to as Local Area Wireless Network(LAWN)
- 25. WLANs cont.. Wi-Fi • Is a local area wireless technology that allows an electronic device to exchange data or connect to the internet using 2.4 GHz UHF and 5 GHz SHF radio waves. Types of wireless LANs.. • Peer-to-peer • Bridge • Wireless distribution system
- 26. Types of wireless LANs Peer-to-peer • An ad hoc network is a network where stations communicate only peer to peer (P2P) • There is no base and no one gives permission to talk. • A peer-to-peer network allows wireless devices to directly communicate with each other. Bridge • A bridge can be used to connect networks, typically of different types. • The bridge acts as the connection point to the Wireless LAN • There are four types of network bridging technologies: - Simple bridging - Multiport bridging - Learning, or transparent bridging - Source route bridging
- 27. Types of wireless LANs Wireless distribution system • Enables the wireless interconnection of access points in an IEEE 802.11 network. • allows a wireless network to be expanded using multiple access points without the need for a wired backbone to link them, as is traditionally required. • Preserves the MAC addresses of client packets across links between access points.
- 28. Wireless mesh network Wireless network made up of radio nodes organized in a mesh topology. Each node forwards messages on behalf of the other nodes. Mesh networks can "self heal", automatically re-routing around a node that has lost power. Wireless mesh networking could allow people living in remote areas and small businesses operating in rural neighborhoods to connect their networks together for affordable Internet connections.
- 29. Wireless Metropolitan Area Networks(WMANs) Officially known as IEEE 802.16, complement other wireless technologies like Wi-Fi. Use in large, city-sized wireless networks that can deliver broadband Internet access and compete against wired technologies like Digital Subscriber Line (DSL) and cable modems. WirelessMAN standards form the basis for WiMAX and several other wireless broadband technologies. Known as a point to multipoint setup. The maximum distance for this type of network is about 30 miles (48 km)
- 30. WMANs cont.. Types of WMANs, - Back Haul • For enterprise networks, cellular tower connection and Wi-Fi hotspots. • an option for enterprises that can't afford to install or lease fiber to connect their facilities over a large campus or city. - Last Mile • Could establish wireless as an alternative to residential broadband DSL/cable modem. • Last-mile WMANs are suits for temporary networks, such as large construction sites or areas where conventional network service is disrupted.
- 31. Wireless Wide Area Networks(WWANs) Typically cover large areas, such as between neighboring towns and cities, or city and suburb. Also called "wireless broadband" or "broadband wireless”. Wireless WANs use cell towers to transmit a radio signal within a range of several miles to a moving or stationary device. There are 3 major wireless WAN technologies, • GSM • CDMA • WiMAX - newer Traditional cellular systems
- 32. Cellular network Radio network distributed over land areas called cells. In a cellular network, each cell characteristically uses a different set of radio frequencies from all their immediate neighboring cells to avoid any interference. When joined together these cells provide radio coverage over a wide geographic area.
- 33. Global Area Network(GAN) A network used for supporting mobile across an arbitrary number of wireless LANs, satellite coverage areas, etc. The key challenge in mobile communications is handing off user communications from one local coverage area to the next.
- 34. Space network Established in the early 1980s to replace NASA's worldwide network of ground tracking stations Used for communication between spacecraft. Space Network is operated 24 hours a day, seven days a week, 365 days per year. The Space Network consist of: • A constellation of geosynchronous (Earth orbiting) satellites named the Tracking Data Relay Satellite (TDRS) • Ground systems that operate as a relay system between satellites. • Satellites in low Earth orbit (LEO) above 73 km • Ground facilities
- 35. References • ftp://ftp.iol.unh.edu/pub/bfc/UNH-IOL_BFC_Knowledgebase_Bridging.ppt • http://web.mst.edu/~mobildat/wman/ • http://searchnetworking.techtarget.com/definition/wireless-mesh-network • http://en.wikipedia.org/wiki/Wireless_mesh_network • http://searchnetworking.techtarget.com/definition/wireless-mesh-network • http://en.wikipedia.org/wiki/Wireless_LAN • http://en.wikipedia.org/wiki/Wireless_network#Wireless_MAN • http://www.wisegeek.com/what-is-wirelessman.htm • http://www.nasa.gov/directorates/heo/scan/services/networks/txt_sn.html# .U-cuLPldWN4
- 36. IPv4 and IPv6 Coexistence
- 37. Overview Address space in IPv4 is running out and it will completely run out very soon. There are three strategies for IPv6 transition • Dual Stack Network The original strategy Depends on sufficient IPv4 being available • 6rd (Rapid Deploy) Improvement on 6to4 for SP customer deployment Activity of IETF Softwires Working Group • Large Scale NAT (LSN) SP deploys large NAT boxes to do address and/or protocol translation Functionalities and operational issues of this coexistence. Potential scenarios of transition and recommendations for transition.
- 38. Why should we care of IPv4/IPv6 coexistence and transition?
- 39. Is IPv4 really running out? Yes ! • IANA IPv4 free pool ran out on 3rd February 2011 • RIR IPv4 free pool will run out soon after. The runout gadgets and widgets are now watching when the RIR pools will run out: • inetcore.com/project/ipv4ec/index_en.html • ipv6.he.net/statistics/
- 40. Strategies available for Service Providers Do nothing • Wait and see what competitors do • Business not growing, so don’t care what happens Extend life of IPv4 • Force customers to NAT • Buy IPv4 address space on the marketplace Deploy IPv6 • Dual-stack infrastructure • IPv6 and NATed IPv4 for customers • 6rd (Rapid Deploy) with native or NATed IPv4 for customers • Or various other combinations of IPv6, IPv4 and NAT
- 41. Dual-stack network Both IPv4 and IPv6 have been fully deployed across all the infrastructure • Routing protocols handle IPv4 and IPv6 • Content, application, and services available on IPv4 and IPv6 End-users use dual-stack network transparently • If DNS returns IPv6 address for domain name query, IPv6 transport is used • If no IPv6 address returned, DNS is queried for IPv4 address, and IPv4 transport is used instead It is envisaged that the Internet will operate dual stack for many years to come
- 42. Dual-stack network cont.. Advantages • Support ensures any-to-any communications • regardless of the versions of IP Disadvantages • Double the communications processing requirements of all of the network resources. • This leads to performance degradation • IPv6 on existing IPv4 infrastructure might cost extra in terms of hardware changes
- 43. 6rd (Rapid Deploy) 6rd (Rapid Deploy) used where ISP infrastructure to customer is not IPv6 capable (eg IPv4-only BRAS) • Customer has IPv4 Internet access either natively or via NAT • Customer IPv6 address space based on ISP IPv4 block
- 44. 6rd (Rapid Deploy) cont.. Advantages • The service provider has a relatively quick way of providing IPv6 to their customer without deploying IPv6 across their infrastructure. • Subscribers can readily get access to IPv6 • 6rd relay and CPE are becoming available from vendors Disadvantages • 6rd is not a long-term solution for transitioning to IPv6 – one further transition step to remove the tunnels • CPE needs to be upgraded to support 6rd • The ISP has to deploy one or several 6rd termination devices • If customer or SP uses NAT for IPv4, all NAT disadvantages are inherited
- 45. Large Scale NAT (LSN) Also known as Carrier-grade NAT (CGN) Translates private IPv4 addresses into public IPv4 addresses. CGN employs Network Address and Port Translation methods to aggregate multiple private IPv4 addresses into fewer public IPv4 addresses.
- 46. Dual-Stack lite (DS-Lite) was specified in RFC 6333, "Dual-Stack Lite Broadband Deployments Following IPv4 Exhaustion", August 2011. Technically DS-Lite involves more than just tunneling But the IPv6 Forum includes it under the tunnel transition mechanism in their training curriculum
- 47. DS-Lite cont.. Advantages • The service provider is using IPv6 across its entire infrastructure, avoiding the IPv4 depletion problem in the network. • IPv6-only infrastructure in an ISP ensures that the ISP can carry on scaling its infrastructure without dependency on IPv4 address resources. • Consumers can transition from IPv4 to IPv6 without any requirement to be aware of the differences between the protocols. Disadvantages • The service provider needs to buy, install, and run a CGN that supports DS-Lite. • The CGN must keep NAT44 states (please note that MAP is a promising technology alleviating this drawback).
- 48. Functionalities and Operational Issues Complexity of operation: • Moderate in the case of a single network with two address families Complexity of troubleshooting: • Running two address families and/or tunnels is assumed to be more complex Breaks end-to-end connectivity in IPv4: • Subscribers sharing a CGN will have little to no hurdles in their communication • Subscribers separated by one or several CGN will experience some application issues
- 49. Potential scenarios Most of the content and applications move to IPv6 only Most of the content and applications are offered for IPv4 and IPv6 Most of the users move to IPv6 only • Especially mobile operators offering LTE handsets in emerging countries No change (the contents/applications stay IPv4 and absence of pro-IPv6 regulation), SP customer expectations devolve to double-NAT No change (the contents/applications stay IPv4) but SP customer expectations do not devolve to double-NAT (or they are ready to pay for peer-to-peer connectivity) • Perhaps well established broadband markets like US or Europe
- 50. Recommendations 1. Start deploying IPv6 as long term strategy 2. Evaluate current addressing usage to understand if IPv4 to IPv4 NAT is sufficient for transition period 3. Prepare a translation mechanism from the IPv4 Internet to the IPv6 Internet 4. Educate your user base on IPv6 introduction, the use cases and troubleshooting
- 51. Summary
- 52. References www.potaroo.net/tools/ipv4/ inetcore.com/project/ipv4ec/index_en.html ipv6.he.net/statistics/ http://www.networkworld.com/article/2232181/cisco- subnet/understanding-dual-stack-lite.html http://www.cisco.com/c/en/us/products/collateral/ios-nx-os- software/enterprise-ipv6-solution/whitepaper_c11- 698132.pdf http://en.wikipedia.org/wiki/Carrier-grade_NAT
Editor's Notes
- #4: Interconnecting media is, The media through which the signals propagate is of great importance within the Ethernet network system. It governs the majority of the properties that determine the speed at which the data may be transmitted. The network nodes are the points to and from which the communication takes place
- #5: DTE devices are either the source or destination of the data being sent. Devices such as PCs, file servers, print servers and the like fall into this category. DCE Devices that fall into this category receive and forward the data frames across the network, and they may often be referred to as 'Intermediate Network Devices' or Intermediate Nodes. They include items such as repeaters, routers, switches or even modems and other communications interface units.
- #6: Point to Point is the simplest configuration as only two network units are used. It may be a DTE to DTE, DTE to DCE, or even a DCE to DCE.
- #7: Coaxial bus type of Ethernet network is rarely used these days. The systems used a coaxial cable where the network units were located along the length of the cable. The segment lengths were limited to a maximum of 500 meters.
- #8: Star network consists of a central network unit, which may be what is termed a multi-port repeater or hub, or a network switch. All the connections to other nodes radiate out from this and are point to point links.
- #11: Using Ethernet to connect LANs to Metro Area Networks (MANs) and WANs can help reduce capital expenses and operating expenses in several ways. Many Ethernet service providers allow customers to connect their business networks in ways that are either more complex or impossible with legacy services. As opposed to regular Internet traffic, carrier Ethernet that runs at Layer 2 does not have a standard Layer 3 protocol attached to it,this allows for users to run the protocol of their choice over their Ethernet connection (IPv4, IPv6, both, or another Layer 3 protocol). Due to the length of time Ethernet has been in existence and the fact that much of a WAN is managed by a 3rd party, it is relatively easy to set up. Most of the WAN is managed by a 3rd party. As a benefit, the user adopts the ISP’s backbone as part of their network thus the reliability associated with the providers network is adopted into the user’s WAN. Ethernet is now supported by more than 60 service providers and 100 equipment manufacturers, making Ethernet available in thousands of cities around the world.
- #21: A wireless network is any type of computer network that uses wireless data connections for connecting network nodes. This method is very useful which homes, telecommunications networks and business installations avoid the costly process of introducing cables into building To make connection between various equipment locations, this wireless network technologies are very useful
- #22: PAN is a computer network organized around an individual person. WPANs address wireless networking and mobile computing devices such as PCs, PDAs, peripherals, cell phones, pagers and consumer electronics. The main WPAN technology is Bluetooth For example, a laptop can be connected to the Internet wirelessly by creating a Bluetooth WPAN with a cell phone.
- #23: Infrared radiation was discovered in 1800 by astronomer William Herschel
- #24: ZigBee is the only standards-based wireless technology designed to address the unique needs of low-cost, low-power wireless sensor and control networks in just about any market.
- #28: An access point can be either a main, relay, or remote base station. All base stations in a Wireless Distribution System must be configured to use the same radio channel, and share WEP keys or WPA keys if they are used. They can be configured to different service set identifiers.
- #29: Wireless mesh networks can be implemented with various wireless technology including 802.11, 802.15, 802.16, cellular technologies or combinations of more than one type.
- #32: The wireless connections between access points are usually point to point microwave links using parabolic dishes on the 2.4 GHz band, rather than omnidirectional antennas used with smaller networks
- #33: Radio coverage enables a large number of portable transceivers (e.g., mobile phones, pagers, etc.) to communicate with each other and with fixed transceivers and telephones anywhere in the network, via base stations, even if some of the transceivers are moving through more than one cell during transmission.
- #45: As advantage : 6rd operation is completely stateless, does not have the operational drawbacks of 6to4, and does not postpone IPv6 deployment
- #47: Dual-Stack lite was designed to let an Internet service provider omit the deployment of any IPv4 address to the customer's Customer-premises equipment (CPE).