Skip to main content

GRE Protocol

The Generic Routing Encapsulation (GRE), specified in [RFC2784], is an IETF standard defining multi-protocol encapsulation format that could be suitable to tunnel any network layer protocol over any network layer protocol. This concept was originally specified in [RFC 1701], which was an informational RFC. When this original protocol was moved to a standards track, the decision was made to replace it with two separate RFCs: [RFC2784] and [RFC2890]. [RFC2890] is an extension of the basic GRE header described in [RFC2784]. It was determined necessary because [RFC 2784] does not lend itself to encapsulation of PPP frames, since it does not have a sequence number in the GRE encapsulation format. This limitation was removed by adding a sequence number extension to the basic GRE header. Also, [RFC2784] does not allow for multiplexing onto the same GRE tunnel of tunneled packets belonging to different administrative entities possibly adopting overlapping private address spaces (a very useful feature for the provision of Virtual Private Networks). This limitation was also removed by adding a key field—that is, a numeric value used to uniquely identify a logically correlated flow of packets within the GRE tunnel—as an extension of the basic GRE header. These extensions to a basic GRE defined by [RFC2890] were especially useful in wireless data communications. For example, they allowed for in-sequence delivery of PPP frames over the R-P interface in CDMA2000 (see Chapters 4 and 7 for more details), and the provisioning of compulsory MVPN services.
GRE, as defined by these RFCs, is normally used in two classes of applications: the transport of different protocols between IP networks and the provision of VPN services for networks configured with potentially overlapping private address space. The GRE header key field can be used to discriminate the identity of the customer network where encapsulated packets originate. In this way, it provides a way to offer many virtual interfaces to customer networks on a single GRE tunnel endpoint. This feature allows for policy-based routing (that is, when routing decisions are not based only on the destination IP address but on the combination of a virtual interface identifier, and service desk salary the destination IP address) and relatively easy per-user network accounting. Also, a GRE header allows the identification of the type of the protocol that is being carried over the GRE tunnel, thus allowing IP networks to serve as a bearer service onto which a virtual multi-protocol network can be defined and implemented.

Comments

Post a Comment

Popular posts from this blog

Upcoming Wireless Network technology

For a significant part of the historical backdrop of remote systems, huge media communications organizations have driven the vast majority of the adjustments in the business. That example proceeds with today, and huge organizations will keep on having considerable impact into what's to come. In this day and age, however, little organizations have a superior possibility than any time in recent memory of disturbing the business, and many are progressing in the direction of that. We have additionally observed some new enormous organizations make moves into the remote space as of late. Remote has the benefit of not requiring the monstrous foundation speculations of wired systems, which opens up the market to littler organizations. This likewise makes it progressively attainable for enormous organizations, just as clients, to change to remote items. Remote advancements likewise make it simpler to grow Internet access to zones that were difficult to reach with wired tech. Facebook, ...
Post a Comment
Read more

Development of Future Networking Technologies

Web broadcast communications innovation has been hot and will keep on commanding the enthusiasm of the two purchasers and business experts the same. Transfer speed is as yet the significant bottleneck for a large number of us getting to the Internet, so new transmission strategies must be conceived. These transmission strategies must furnish us with cheap data transfer capacity that is anything but difficult to utilize and simple to set up. This part is separated into six segments, trailed by a salute to the future and my goodbye to this book. Area one ganders at potential Internet advancement beginning with Internet2 and the most recent rendition of Internet convention IPV6. Segment two looks at rapid transmission innovations, which incorporate improvement of fiber transmission lines and some new spine link innovation called photonic fiber. Segment three is committed to communicate transmission or improvements to radio and TV as we probably am aware it today. Absolutely, ther...
Post a Comment
Read more

Why 5G is the heart of Industry 4.0

We are in the fourth mechanical unrest. Numerous business heads are focusing on vitality utilization and mechanization, yet is 5G the genuine driver of Industry 4.0? The reason of Industry 4.0 is about the marriage of physical and computerized advances. With Industry 4.0, makers can utilize associated frameworks to increase basic bits of knowledge about their tasks. These bits of knowledge can be utilized to improve operational productivity. A subset of Industry 4.0 is savvy fabricating, characterized by The National Institute of Standards and Technology (NIST) as frameworks that seem to be "completely coordinated, shared assembling frameworks that react progressively to fulfill changing needs and conditions in the manufacturing plant, in the inventory arrange, and in client needs." With the up and coming age of the mechanical insurgency being activated by the mix of developing innovation, the effect that 5G has on Industry 4.0 will be novel. As a pattern itself, 5G won...
Post a Comment
Read more

Gig Economy Telecom Work Force