4.3 The Internet Protocol, part 2

Video presentation: Network Layer: The Internet Protocol, part 2. Network address translation. NAT. IPv6. Tunneling.
Computer networks class.
Jim Kurose
Textbook reading: Section 4.3.3 and 4.3.4, Computer Networking: a Top-Down Approach (8th edition), J.F. Kurose, K.W. Ross, Pearson, 2020.
See gaia.cs.umass.edu/kurose_ross for more open student resources.

[@JustinHalford]

Thanks to these videos, I have gone from 0 to familiar with the first half of your text's contents in 2 days! You are an incredible teacher.

[@dayssnow1049]

Importance of Network Address Translation and IPv6 in Managing IPv4 Address Space
00:13 Network Address Translation (NAT) and IPv6 address space are key to overcoming IPv4 limitations
02:41 Network Address Translation (NAT) provides advantages such as security and flexibility.
05:08 Network Address Translation (NAT) process and implications
07:34 IPv6 was motivated by the need for a larger address space and introduced innovations like tunneling and flow labels.
10:02 IPv6 header has no checksum, fragmentation, reassembly, or options fields, and allows for faster processing.
12:36 Tunneling allows IPv6 routers to forward IP Datagrams over IPv4 networks.
15:14 IPv4 network acts as a tunnel for IPv6 communication
17:53 Tunneling allows co-existence of IPv4 and IPv6 for end-to-end datagram forwarding.
20:03 Internet Protocol IP is crucial for the Internet's network layer.

[@bobjones1196]

Theres no other feeling like understanding a concept that is so unique and beautiful and elegent, it is only made possible by professors like you! Tunneling is an art

[@DesTorix]

You are a great lecturer! I am baffled over and over again during the course of these lectures on how smart the solutions to lets say the IPv4 Problem is.

[@ricp]

Excellent lecture! Thanks so much for the great explanations, Sir.

[@hoang-himself]

ISPs just hate giving IPv6 addresses with prefix less than /64
I need /56 or /60 for my subrouters

[@xagent6327]

One quick Question. How does the router know that the next hop router is of type IPv4, So i need to encapsulate it into an IPv4 datagram

[@christio02]

Probably because its both IPv6/IPv4, and knows that its connected to the next IPv6 router via a IPv4 tunnel

[@bobjones1196]

its known because of the forwarding table. The forwarding table will tell you the next hop's IP and version type.

[@solomontan1524]

At 17:20, shouldnt it be B-to-C, C-to-D and D-to-E instead of B-to-C, B-to-C, B-to-C?

[@emmanuelu]

has to be a typo

[@KBrown2480]

No, I believe it has to keep its original source address. The source of that datagram was still B (where it was created), though it wasn't its directly connected partner

[@solomontan1524]

@@KBrown2480 you misunderstand. I am not referring to the src and dest fields in the red boxes. I am referring to the lines below the three red boxes.

[@jeffersonnguechoum3590]

Yeah it is . I think it’s a typo

[@tahaelaminekassabi5720]

the flow label is 20 bits long!!

[@tamaricashaw6967]

7:36

[@klevisimeri607]

🧠

[@MuddafukhingdisKUST]

this is an excellent series of lectures, thank you!