It provides the ability to switch packets through a. Identify cisco express forwarding concepts ccnp 300101. The line cards can perform the express forwarding by themselves, relieving the main processor. Pbr with route maps 114 cisco ios ip service level agreements 115 step 1.
Before discussing cef one needs to be familiar with how a router actually routes a packet, these are the steps summarized. Changes to the routing table and next hop ips are reflected in the fib. Unicast, out of order packets, asymmetric routing describe ip operations i. Cisco express forwarding cef the most recent, fastest, and preferred cisco ios packetforwarding mechanism. Oct 23, 2018 this video is about the below ccnp route exam version 2 topics. Ccnp routing and switching portable command guide, 2e. A switching mechanism that incorporates the fib and adjacency tables into the switching process.
Delivered online in html and pdf format access, bookmark, and add notations from your pc, mac, ios, or android device no restrictions on access, printing, or time limits continual development cycle ensures that you always. Forwarding information base the fib is used to make layer3 ip destination prefixbased switching decisions. Mengikut pehaman daripada pembacaan, cef ini adalah untuk mempercepatkan lagi data processing pada router. Cisco confidential 11 process switching an older packet forwarding mechanism still available for cisco routers.
Here is the cisco definition of epoch and how it is used. It is an advanced one in layer 3 switching technology, which is mainly used in the internet or else core networks to enrich the overall performance of the network. Fast switching the initial packets forwarding decision is still derived from the route processor, but that destination is then held in cache for subsequent forwarding precluding the processors involvement. The first packet to a particular destination is process switches, then those results are stored in the fast route cache. Cisco isr 2900 series routers running ios version 15. Nov 12, 2017 cisco has created two optimization methods called fast switching and cisco express forwarding cef to speed up the process.
The exam is notoriously difficult and ccie candidates must first pass a. Apr 19, 2014 cisco express forwarding cef is advanced, layer 3 ip switching technology. Information about implementing cisco express forwarding software toimplementciscoexpressforwardingfeaturesinthisdocumentyoumustunderstandthefollowingconcepts. Initial switch configuration and verifying network status and switch operation using basic utilities such as ping, telnet and ssh. This cef also optimizes the scalability for the networks with a dynamic and large traffic pattern. This can be done because cef maintains two tables in the data plane. This is the only switching method available on the cisco 12000 series router.
Cisco express forwarding demystifies the internal workings of cisco routers and switches, making it easier for you to optimize performance and troubleshoot issues that arise in cisco network environments. Icmp unreachable and redirects, ipv4 and ipv6 fragmentation, ttl explain tcp operations i. The time after this instant is in an epoch different from the time before, and the different epochs are numbered between 0 and 255. This book addresses common misconceptions about cef and packet switching across various platforms, helping you to improve your. Jan 17, 2006 cisco express forwarding cef switching is a proprietary form of scalable switching intended to tackle the problems associated with demand caching. Identify cisco express forwarding concepts routing implement and troubleshoot device access explain general network challenges compare routing protocol types control explain ip operations implement, optimize and troubleshoot implement and troubleshoot control plane explain tcp operations administrative distance policing. Cisco express forwarding cef provides the ability to switch packets through a device in a very quick and efficient way while also keeping the load on the routers processor low. Cisco express forwarding cef switching is a proprietary form of scalable switching intended to tackle the problems associated with demand caching. Network principles identify cisco express forwarding concepts o fib o adjacency table explain general network challenges o unicast o outoforder packets o asymmetric routing describe ip operations o icmp unreachable and redirects. Cisco s implementation of this architecture is know as cisco express forwarding cef process switching the routermls processes every packet to make a forwarding decision.
The time after this instant is in an epoch different from the time before, and the. These are automatically updated at the same time as. The main purpose of cef is to optimize the forwarding of packets and increase the packet switching speed. Although cef is a cisco proprietary protocol other vendors of multilayer switches or highcapacity routers offer a similar functionality where layer3 switching or routing is done in hardware in an asic instead of by. Most popular cisco 300101 pdf and video exam preparation. Ccnp route master study guide quizlet flashcards 1. Most popular cisco 300101 pdf and video exam preparation materials ccdp, cisco february 7, 2017, by testsectd comments off. Fast switching works by caching results to a destination. Table entries are not packettriggered like fast switching but change triggered. A new epoch for a cisco express forwarding table begins when a table rebuild is initiated.
Cisco express forwarding cef fastest, most recent, and preferred packetforwarding mechanism cef builds a forwarding information base fib and an adjacency table table entries are not packettriggered like fast switching, but changetriggered when something changes in the network topology. With cef switching, the information which is conventionally stored in a route cache is split up over several data structures. Cisco express forwarding cefshown in figure 110, cef is the most recent and preferred cisco ios packetforwarding mechanism. Identify cisco express forwarding concepts fib adjacency table explain general network challenges unicast outoforder packets asymmetric routing describe ip operations icmp unreachable and redirects ipv4 and ipv6 fragmentation ttl.
The cef is most often used to improve the speed of the packet switching by deducting the overhead as well as delays which is introduced by means of other routing techniques. Control plane and forwarding plane impact to troubleshooting and performances excluding specific platforms architecture o identify cisco express forwarding concepts rib, fib, lfib, adjacency table load balancing hash polarization concept and avoidance o explain general network challenges unicast flooding out of order packets. Identify cisco express forwarding concepts explain general network challenges i. Cisco route certification exam syllabus and preparation guide. Verifying cisco express forwarding 111 configuring cisco express forwarding 111 path control with policybased routing 112 verifying policybased routing 1 configuration example. Cisco 300101 practice exam identify cisco express forwarding concepts test. This video is about the below ccnp route exam version 2 topics. Cef optimizes network performance and scalability for networks with large and dynamic traffic patterns, such as the. He was a technical contributor and editor of a number of ieee 802 standards, including 802. Ccnpccnp the best cisco ccna,ccnp,linux training in pune. Cisco express forwarding cef is a packetswitching technique that is the default for many of ciscos router lines over the last ten years. Data plane responsible for moving data from ingress to egress. Cisco express forwarding concepts and challenges in general network. Cisco express forwarding cef is an advanced layer 3 switching technology used mainly in large core networks or the internet to enhance the overall network performance.
Ccie routing and switching certification guide, 4th. Although cef is a cisco proprietary protocol other vendors of multilayer switches or highcapacity routers offer a similar functionality where layer3 switching or routing is. Fast switching a common packet forwarding mechanism which uses a fastswitching cache to store next hop information. With cef, none of the packets are sent to the cpu to be switched. The ccie routing and switching certification is the most respected certification in the industry.
Routers once had combined control planes and data planes. Section weight objectives network principles 10% 1 identify cisco express forwarding concepts a fib b adjacency table 2 explain general network challenges a unicast b outoforder packets c asymmetric routing 3 describe ip operations a icmp unreachable and redirects. The process of configuring and verifying vlans and describe how vlans create logically separate networks and the need for routing between them. Like fast switching, cef builds a forwarding information base fib, and an adjacency table. The cef code is able to maintain these data structures in the gigabit. Control plane creates and maintains the routing table. Ipv4 and ipv6 pmtu, mss latency, windowing, bandwidthdelay product, global. Packet is received, frame check sequence fcs is checked, if passed it moves to step 2. Identify cisco express forwarding concepts ccie wiki. Our team of experts has composed this cisco 300101 exam preparation guide to provide the overview about cisco implementing cisco ip routing exam, study material, sample questions, practice exam and ways to interpret the exam objectives to help you assess your readiness for the cisco route exam by identifying prerequisite areas of knowledge. Describe basic software architecture differences between ios and ios xe identify cisco express forwarding concepts explain general network challenges explain ip, tcp and udp operations describe chassis virtualization and aggregation technologies explain pim snooping describe wan ratebased ethernet circuits.
Cisco express forwarding cef is a packetswitching technique used within cisco routers. Key features supported in the cisco express forwarding implementation thefollowingfeaturesaresupportedforcefonciscoiosxrsoftware. Feb 27, 20 cisco express forwarding cef is a packetswitching technique that is the default for many of ciscos router lines over the last ten years. Describe the process of configuring and verifying trunking on cisco. Cisco route certification exam syllabus and preparation. Exsimmax for cisco 300101 route exam simulation software covers all of the concepts you need to know to pass the cisco 300101 route exam. Cisco express forwarding is a switching method developed by cisco, this switching method is the fastest that can be used on a cisco device.
Cisco express forwarding cef is advanced, layer 3 ip switching technology. The 300101 route practice exam includes wellwritten, technically accurate questions and answers, which are divided into three individual exam simulations. Adjacency table is populated with l2 next hop addresses for all fib entries arp, framerelay mappings. Prior to cef there were 2 methods for packetswitching process switching and fastswitching. The successful ccie candidate must understand a broad range of network technologies that includes osi model, bridging, lan switching, ip and ip routing protocols, multicast, wan technologies, and performance management.
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