CCIE Routing and Switching (R&S) 400-101 V5.1 Written Exam: Explain General Network ChallengesPaul Adam
In this article, I will be discussing Cisco General Network Challenges as part of network Principal and Network Theory CCIE Routing and Switching (R&S) V5.1 exam blueprint topics.
- Explain general network challenges
- Unicast flooding
- Out of order packets
- Asymmetric routing
- Impact of micro burst
Let me summarize some of the key takeaways related to Cisco General Network Challenges as relevant to CCIE Routing and Switching (R&S) V5.1 exam blueprint topics.
General Network Challenges Exam Essentials
- Tail drops, in a show interface CLI, are a sign that microbursts may be occurring
- When TCP flows are combined with UDP flows within a single class and the class experiences congestion, TCP flows continually lower their transmission rates due to congestion control, potentially giving up their bandwidth to UDP flows that are oblivious to drops. This effect is called TCP starvation or UDP dominance
- Configuration of portfast on all end-device ports (such as printers, PCs, servers, and so on) should limit TCNs to a low amount
- The primary reasons for unicast flooding behavior include asymmetric routing, STP topology changes (as evident with repeated TCNs), and MAC forwarding table overflow.
- Using per-packet load balancing to share the traffic load across available paths to a given destination can cause out-of-sequence packets in a particular data flow. This can result in unsatisfactory data transmission for video and voice streaming traffic.
- Micro-bursting is a behavior where rapid bursts of data packets are sent in quick succession, leading to periods of full line-rate transmission that can overflow packet buffers of the network stack, both in network endpoints and routers and switches inside the network.
I sincerely hope that you found this video helpful. Please post your questions or suggestions in the comments and tell me how you are preparing for your CCIE Routing and Switching (R&S) V5.1 written and lab exams.