GRE And GRE Tunneling: Configuration and Importance

What is Generic Routing Encapsulation (GRE)?

Generic Routing Encapsulation (GRE) is a well-known tunneling technology developed by Cisco Systems in the late 1990s which enables various types of devices to securely tunnel through IP networks.

It was chosen for its security properties as well as for its ease of use, making it one of the most widely used and recommended solutions in the information communications industry.

Basically, GRE is a compacted version of the classic Layer 2 Virtual Address Protocol (VAPR), and the same network providers can associate many different traffic models with a single IP address.

For instance, when a business uses a web interface to present its products to customers, it is only necessary for them to have their IP addresses in the form of GRE fields and associate these addresses with the relevant traffic model. This makes it very easy for all IT service providers and web hosts to create secure IP-based tunnels for both standard and application-specific functions.

The advantage of using generic routing encapsulation techniques is the fact that it provides IP-based services and allows for flexible negotiation between various protocols.

Basically, IP networks use the Internet to transport packets of information. The packet format that the Internet uses is well-known as TCP/IP. These packets include IP header along with the MAC address and the header padding, which are also used for authentication and integrity purposes.

Any packet that has an IP header and a MAC address will be able to gain a session identifier, referred to as Session ID, which is used to provide authentication and authorization purposes.

The major components of the generic routing encapsulation include the following: Checksum field, which controls and distinguishes checksum values, a random-number generator, and an encryption algorithm.

The checksum field contains valid information hence, it should be random and unique according to the type of service used. The random number generator will generate random numbers that are independent of one another and thus will produce indistinguishable numbers during transmission. The algorithm will be used to encrypt and authenticate all the data that is encapsulated within the packets.

When you use a generic routing encryption technique, there is no need for companies to purchase different encryption tools and hardware for the purpose of protecting their traffic.

Hence, the company does not have to spend money on buying and equipping its internal systems for proper protection.

Benefits of using GRE protocols

There are many threats to a company’s networking systems from hackers and other unauthorized parties. A generic routing tool is an ideal solution to prevent unauthorized access to company data because it provides a high level of security at a low cost.

There are several advantages of using a generic routing software package and these are mainly evident when it comes to saving on time and money.

Companies are able to maintain their efficiency levels thanks to this method and the best part about it is that the entire process does not require manual intervention.

Another advantage is that the security level is high as the traffic is protected using different ports which only means that any data or packet of security is transmitted safely and effectively.

GRE can help protect a company’s network from all threats. This is achieved by intercepting data packets that are carrying sensitive information before they reach their destination.

Once the packets are intercepted, they are encrypted so that they cannot be deciphered again once they reach the final destination. Thus, it ensures that a company’s data is absolutely secure, no matter what internet protocol (IP) or network operating system (NOS) is used by the company’s internal system.

Using GRE-capable software enables any IT professional to monitor a company’s security better than a dedicated administrator ever could.

With this kind of technology, an IT professional can make sure that all packets of data sent to and received by a company’s network are secure and encrypted before they reach their destination in both directions.

In addition, this type of software also allows IT professionals to determine if there has been any unusual traffic that originated from or inside the company’s network.

Companies who make use of generic routing encryption tunneling will only have to pay for the tools themselves.

Any organizations that need to set up a whole network infrastructure will also save a lot of money, as they will not need to rent or purchase costly IP servers and other expensive hardware before they can get the job done.

Finally, as long as the organization utilizes a reliable network provider, it will be able to enjoy fast and reliable delivery of applications and files.

All these advantages can be availed at relatively low costs and with ease as well thanks to the internet technology.

Hence, this method can prove to be extremely beneficial for all types of businesses using internet connections and the only thing that one needs to do is to ensure that the network used for transferring large volumes of data or information is updated regularly.

What is GRE Tunneling

GRE tunneling is the encapsulation of packets within a packet. GRE Tunnelling can be set up between two routers.  The routers send and receive GRE packets directly. Only these two routers will be able to open these encapsulated packets, any routers present in between will only forward the packets by referencing the headers surrounding them.

Configuration of GRE Tunneling

Generic Routing Encapsulation (GRES) is an effective tunneling technology that envelops different network-level protocols within a virtual private point-to-point link over an IP network.

At each end, the two common network protocols used as components of the virtual private LAN are identified and the two physical IP network IP addresses are mapped with the help of a trusted source.

The purpose behind this application of the GRE is to create a secured VPN or Local Area Network. This is accomplished by allowing the two or more different network protocols to operate in a transparent manner.

The various modes of operation include static, secure, and anonymous sessions. It also allows the use of GRE alone or in conjunction with IPsec or L2TP/IPsec and PPTP as well as ISMP.

With the advent of Wide Area Networks (WANs), it has become a necessity for all organizations to configure GRE tunneling on their WANs to secure their networks.

An organization can opt to use either the Wired Equivalent Privacy (WEP) or the Wi-Fi Equivalent Privacy (WEP/WEP). Both the technologies provide excellent security and manageability but there are differences between the two.

On the other hand, GRE tunneling is quite a complex process. It involves the configuration of the physical layer of the networking equipment, creation of the IP address, assignment of the IP addresses, and the configuration of the port numbers to connect the GRE devices with the outside world.

Once these are done, the IP packets are transmitted from the client computer to the configured remote site. The whole process of GRE tunneling requires the use of the IP address and the port numbers which are commonly set by the users. There are some additional factors like port forwarding, the STUN, and ACAP options that must be checked while using GRE tunneling.

Configuring GRE over UPnP is easy but you need to take care of certain things like disabling the port blocking devices and also disable the firewall on the local computer or router.

Before going for the tunneling, the following things should be enabled like enabling the policy for a secure connection, type of passwords, and also forwarding the private network packets.

After configuring these things there should be a gateway, it is required for forwarding the traffic from the private network packets to the GRE. You can find many gateways in OS X and you can install them by using the installer installed in OS X.

There are many companies that provide free GRE software and it would be better to install it on computers as the free software is much reliable and secure.

Before going for the installation of the GRE software it would be better to disable the Firewall on the private network interfaces. After the disabling of the firewalls, the next step should be done by configuring the IP and the MAC address.

The MAC address is used as a key for encrypting the public key header of the packets. Similarly, the IP address serves as the key for encapsulating the private network packets and this task can be done by using the IP address from the Network settings utility.

This task also needs to be done before forwarding the traffic from the GRE to the client. The tunnel interface has to be enabled and if you want to know about the GRE port forwarding then you can try using the command ‘digress’ in the terminal and the details of the port forwarding will be given by the tool.

Importance of GRE tunneling

There is much importance on the matter of generic routing encapsulation (guaranteed route) for various industries. The field of business and industry is greatly affected by this.

One of the most significant and fundamental effects of this is that it makes it possible for companies or organizations to save a great amount of money, time, and effort when it comes to providing a certain kind of service or product.

In the case of the business and networks, there is a great need for these services and products. This is because it is quite difficult for a business or network to gain the specific kind of network connectivity required to do work without being able to use it with other companies which are located at different locations.

By using generic routing encapsulation(GRE), these companies are able to gain the kind of service that they require without any difficulty whatsoever. This is important because their work depends on the fast speed and efficient transport of information and communication between different sources in order to get the job done.

This method of service delivery is essential for organizations because they need to gain the connection points at a faster rate which is actually impossible if they were using the old method of linking.

Basically, this new method has brought a revolution in the field of networking as a whole. With this, companies and organizations have been able to save a lot of money and time while making use of a certain kind of medium that is faster than the previous kinds of mediums that were used.

Basically, generic routing encapsulation tunneling is also known as IP changing networking. This method has been widely used for various different types of businesses that are based on internet connections.

The method is able to allow different companies to link their data over a certain distance using a medium that is highly reliable and of course, very fast in the process.

The system enables them to transfer large files through a number of networks by using a single connection and this makes the entire process highly flexible and cost-effective.

As far as the details of this method are concerned, it works on the principle of physical layer multipoint transmission.

Basically, the network must be able to send data packets that can be obtained from different parts of the system using different ports. However, the problem arises when the same packet is sent to more than one part of the system.

Sometimes, this could lead to loss of data packets and thus lower speeds can be experienced. To prevent such situations, the system uses what is known as hop by hop and path types in order to sort out the packets and make sure that they are not lost in any of their stages.

These different stages also help to make sure that no packet is lost in any given portion and this is the reason why the entire network operates at such high-speed levels.

Impact on DDoS protection

Before discussing further its impact on DDoS prevention, let us understand first what the basic definition of DDoS is.

A DDoS attack is an attempt to overload the target computer with network traffic in such a way that it crashes or exceeds the bandwidth limits set for the network. These types of attacks are carried out by using a variety of techniques that are quite complicated and sophisticated and usually rely on state-of-the-art software to perform the task.

The impact of Generic Routing Encapsulation (guessing) on DDoS attacks is a significant one for several reasons.

Damage control:

The aim of a DDoS is to overload a network by using massive amounts of data packets, causing data loss and system downtime. Most experts agree that it is impossible to prevent an attacker from attacking a network, but there are certain measures that can reduce his power to affect the network. These measures allow a network owner to reduce the likelihood of his system being targeted by a DDoS by several measures. GRE is one of the most sophisticated measures that can be taken to reduce the damage done by a DDoS attack to a minimum

Effective network management:

Effective network management minimizes the effect of DDoS attacks by maintaining normal traffic patterns. A DDoS requires massive amounts of data packets so the network must be able to route them easily and quickly. To achieve this, the network must always remain flexible and adaptive. In order to achieve these goals, network management must include a process of traffic analysis and queuing of traffic before it is sent to the application layer.

Establishing connections with other networks:

In order to analyze traffic and avoid unwanted attacks, the application layer must maintain a record of all the relevant information. This record is used by the application layer to determine which data packets need to be dispatched to which destination in order to minimize the risk of being attacked. A DDoS usually results in a huge influx of traffic to a single destination, which makes it very difficult for the network to handle. In order to handle traffic, the network must be able to establish connections with other networks.

The above-mentioned advantages are the primary reasons why many network administrators choose to implement generic routing as a solution for DDoS attacks.


Why Should You Choose BlockDos for GRE Tunnelling?

GRE tunneling in large organizations has a unique characteristic; it can be applied to all layers of an organization. It helps organizations to cut down on cost without compromising the quality. At the same time, it allows the network administrator to define policies for all the internal and external devices. However, in the absence of certain features like security, reliability, and service-level agreements, GRE does not meet the needs of most companies.

GRE tunnel

This is the reason why organizations rely heavily on a service provider that specializes in providing the GRE tunneling services that are required by organizations in order to satisfy their unique needs. When selecting a provider, the following factors have to be kept in mind:

  • Security: No company can afford to compromise its security in order to save money. Therefore, it makes sense to look for a company that provides high security to its customers. There should be authentication and encryption techniques in place at every point where data is being sent or received. All these functions are usually handled by independent specialists. Therefore, it becomes imperative to keep in touch with a company that can handle this aspect of the business.
  • Reliability: When the data is crucial for the smooth functioning of the organization, reliability is a very important factor that cannot be ignored. In this regard, the company should have well-developed systems that ensure data reliability and uptime. The company should also have expert professionals who test and support the applications on a regular basis. Such an organization will surely provide effective solutions to the needs of the organization.
  • Service Level Agreements: When companies are developing new applications, they normally hire consultants to oversee the entire process. These professionals should also sign service level agreements with the organization. Such agreements should lay down the terms and scope of use. Such an agreement will help to protect the interests of the organization and ensure customer satisfaction.
  • Expert Advisors: The organizations that provide generic routing encapsulation services need to have experts in the field. They should also have employees with good knowledge and experience in the field. These employees need to be available round the clock. The organization will also have to make sure that the employees are provided with adequate training. This ensures that the service is delivered as per the needs of the organization.

BlockDos prides itself on having all the above-mentioned qualities. Hence, it should be your go-to choice for all your GRE based needs