IPv6 and layer-3 Switching

As we all know, relevant organizations of the Internet are considering modifying the old architecture and replacing the existing architecture with IPv6.
Some IPv4 addresses. Therefore, it is very important to understand the relationship between IPv6. IPv6 makes it easier to implement
Some methods are used for layer-3 switching. We know that the most basic difference between two hosts is that we must know
The method in which packets are sent to the other party. For TCP/IP networks, the host that does not belong to the same IP subnet is the third layer
When switching, you must first know the address of the other party and send it directly to the other party; or you must know the router/switch of the intermediate device.
Host), which is forwarded by the transit device. If you do not know the recipient's address, the host and the forwarding device must borrow
Helps traditional routing. The first packet for communication between two hosts is forwarded according to the conventional routing.
After a data packet is successfully sent from the source to the destination, the transit device or host knows how to pass the subsequent data packets
Through layer-3 switching, that is, traditional routing is not performed. Therefore, layer-3 Exchange support
The key to IPv6 lies in the processing of the first packet. Currently, two methods are used:
Find a way to use the existing routing protocol in the first packet
Feature memory is used during transmission to facilitate the processing of subsequent packets on the third layer. The other is to add some new protocols.
Low-level exchange of continued data.

IPv6 adds the "stream tag" field in the header to identify the data stream, which can be used by layer-3 exchange sites.
. Therefore, the layer-3 Exchange implemented by the previous method can make good use of this feature, supporting
Data Packet Exchange. The layer-3 Switch using the latter method focuses on the IPv6 considerations of its new protocol. Because
IPv6 is simpler and more direct than IPv4, so as long as the new protocol for layer-3 exchange is not in conflict with IPv6
So IPv6 is not a problem. The corresponding implementation program may need to be tuned to IPv6
Overall, how to comprehensively consider the stream tag and priority during the specific exchange process, so that the real-time stream and the packet with a higher priority
Obtain the expected QOS.

The routing extension options of IPv6 headers provide some powerful new routing functions, including selecting providers based on policies
(Performance and overhead), support for host movement and automatic re-addressing. These new features are not available in IPv4
So we should also consider the implementation scheme of layer-3 switching. After the location of the mobile host changes, we should promptly
Updates swap memory and uses a new swap path.

Although there are some other differences between IPv6 and IPv4, we have made full consideration in the design.
It is the essence of years of operation experience. In general, the Header Format is simpler.
It is simpler and more convenient to handle, and provides support for new technologies.

We still cannot know the wide implementation time of IPv6, which involves existing investment issues. However, the user should have an overview
I noticed the inevitable development trend from IPv4 to IPv6 and understood the relationship between new technologies and IPv6.