According to RFC documents, Douglas Comer's book "Computer networks and internets" and English wikipedia, class E IP addresses are those with leading bits 1111 (values of remaining bits are arbitrary). On the other hand, Cisco's documents and one of IBM Redbooks - "TCP/IP Tutorial and Technical Overview" - define class E addresses as those with leading bits 11110 (fifth highest bit has a fixed value of 0). How to explain this difference? To make matters worse, the definition of class E in this document:
is self contradictory - according to the left side of the diagram (Figure 1) class E is limited to addresses starting with bits 11110 (not 1111), but at the same time the corresponding right side of the diagram implies that the highest octet of class E address can be equal to 254 which is impossible since the highest possible value of the highest octet should be binary 11110111 (decimal 247). I'm confused. Can you please explain it and, if there's indeed an error in your materials, can you fix it?
That's what I thought. Honestly, it's hard to believe such a fundamental error could remain unnoticed for years by so many people. Am I really the first one who spotted it? After all, Cisco is considered one of the most reputable companies in the world as far as computer networks are concerned, so I'd expect high quality training materials from them. Out of curiosity, I'm still waiting for someone from Cisco to explain why their definition differs from the one in RFC.
Cisco DNA Center version 2.2.2.x includes the features and improvements that
New intelligence provides an easy, gradual, and complete adoption of SD-Access. Faster Cisco DNA Center set-up saves time and effort.
When using Cisco cellular modules with a SIM card an APN must be provided. The APN cannot be stored in the SIM card and is supplied by your SIM card provider. Cisco cellular software contains a database of well-known APNs based on the country and ...
Cisco 3850: IOS-XE/Firmware Upgrade
This procedure is aimed at Cisco 3850 switch ONLY.
IOS-XE Bundle Mode is not covered.
9300, 9500 (vanilla & high-performance), ISR 1k, ISR 4k and ASR is not covered.
Listen: https://smarturl.it/CCRS8E46Follow us: twitter.com/ciscochampionsIt’s been several years since the release of Cisco DNA Center, and it’s matured into a complete network management system, an automation and orchestration engine, an AI/ML analy...
The 2021 IT Blog Awards, hosted by Cisco, is now open for submissions. Submit your blog, vlog or podcast today. For more information, including category details, the process, past winners and FAQs, check out: https://www.cisco.com/c/en/us/t...