Configuring Cisco Site to Site IPSec VPN with Dynamic IP Endpoint Cisco Routers

What is ?

Virtual private network
My current Rpi3 is running: Vyatta as SCP client. When you configure a VPN gateway, the steps you take depend on the deployment model that you used to create your virtual network. I have followed the steps exactly and yet none of my machines can connect to the VPN. If things work fine, you may proceed and configure the firewall -obviously you can configure the firewall before you connect the Vyatta machine to the Internet, if you don't want to do that before the firewall was configured- as already said, you can practice in a virtual lab, say using VMware Server. A VPN can also be used to interconnect two similar networks over a dissimilar middle network; for example, two IPv6 networks over an IPv4 network.


IPSec VPN Software Blade

Why could this happen? Chakra 1, 6 26 What sort of error message do you get when you try to connect? Brian Kelley 1, 6 8. RobS 7, 3 31 Will Vousden 24k 7 60 BCA 2, 1 20 Pasi Savolainen 1, 1 15 SQL Server uses tcp, not udp, for all actual communication between client and server.

Brian Kelley Mar 21 '09 at Guffa k 74 Sergej Andrejev 5, 9 53 Saved my life, mate! These things can be done on the Options screen of the login dialog: Now the connection to the sever via VPN works great, I did not change any port numbers. This worked in my case, but would be an issue when readdressing the server. I was having this issue too with SQL Server Sign up or log in Sign up using Google.

Sign up using Facebook. Sign up using Email and Password. These extensions were first described in RFC ESP encrypts all or part of a packet of data in a way that assures confidentiality even though the data travels over the public Internet. It provides data integrity, and offers assurance of the identity of the data's sender authentication. For details, see RFC Ethernet One of the least expensive, most widely deployed networking standards, enabling the transmission of data at 10 million bits per second Mbps , using a specified protocol.

A more recent Ethernet standard, called BaseTx, enables data to be transmitted and received at Mbps. Ethernet address A unique ID number obtained automatically when an Ethernet adapter is added to a computer. This address identifies the machine as a unique communication item and enables direct communications to and from that particular computer.

See also MAC address. Evil twin A wireless access point masquerading as a trusted wireless network. Attackers use an evil twin to trick unsuspecting users into connecting to their network. Once the victim connects, the attacker can steal passwords or other sensitive information by either capturing unencrypted HTTP traffic or using their control of the network traffic to perform convincing phishing attacks. External interface On the Firebox, an Ethernet port intended for connecting to the portion of your network that presents the greatest security risk typically the Internet and any other switches, routers, or servers connected to, but outside, your network.

External network Any network that can connect to yours, with which you have neither a trusted or semi-trusted relationship. For example, a company's employees would typically be trusted on your network, a primary vendor's network might be semi-trusted, but the public Internet would be untrusted — hence, External.

F failover A configuration that allows a secondary machine to take over in the event of a stoppage in the first machine, thus allowing normal use to return or continue.

See also high availability. This is the opposite of fail-open mode, in which a firewall crash opens all traffic in both directions. Fail-shut is the default failure mode of the WatchGuard Firebox System. Derived from the Ethernet See one-way hash function. The extension can help identify the type of file, and often helps a computer know what to do with the file.

For example, if a file is named glossary. Firebox The WatchGuard firewall appliance. Firebox Monitors allows you to keep an eye on bandwidth usage, who has authenticated to the Firebox, what Web sites have been automatically blocked because they sent questionable traffic, and more.

The word "flash" arises from the fact that it can be erased and reprogrammed rapidly, in blocks instead of one byte at a time. See also active mode FTP. Function In programming, a function is part of a program that performs a specific task.

Computer programs usually consist of modules of code. Each module consists of a small part of the program written to perform one specific task. These small, special-purpose chunks of code are called functions. When a program runs, it calls different functions to perform certain tasks. For example, a programmer could write a function to alphabetize a list of names. When the program got to the place where it needed to alphabetize a list of names, the program would call the alphabetizing function, and the function would return the list of names in the correct order.

If those names then had to be inserted into a database, the program might call a different function to accomplish that. See also parameter and Dynamic Link Libraries. G gateway A system that provides access between two or more networks. Gateways are typically used to connect networks that are dissimilar. The Firebox often serves as the gateway between the Internet and your network.

GUI Graphical User Interface The visual representation on a computer screen that allows users to view, enter, or change information. It is characterized by icons and commonly utilizes a mouse, in contrast to a Command Line Interface CLI , which uses strictly text.

H handshake See TCP handshake. The header of a packet is like the envelope of a traditionally-mailed letter, in that it conveys "return address" and "intended recipient" information but is not the real content of the message. Hexadecimal resembles decimal base numbering with the digits 0 through 9, but the decimal equivalents of 10 - 16 are represented in hexadecimal by the letters A through F.

For example, a business might have a master Certificate Authority, which vouches for a Certificate Authority at the company's Los Angeles office, which vouches for a Certificate Authority at the company's Phoenix office.

High Availability High Availability enables the installation of two Fireboxes so that if one fails for any reason, the other takes over immediately. This minimizes data loss while the failed box is replaced or repaired.. Historical Reports A WatchGuard Firebox System application that creates HTML reports of Firebox log files, displaying session types, most active hosts, most used services, and other information useful in monitoring and troubleshooting a network.

The end result is that when you receive a data packet, you can know that whoever sent the packet possesses the same secret key that you do. You can combine this with other technologies, such as IKE , to know who sent a given message. For the Firebox to be able to send data to the host, it must be informed of the existence of the additional router and the host behind it. This entry in the Firebox's routing table is the host route. HTML files are written in plain text, then read or interpreted by a Web browser.

HTTP HyperText Transfer Protocol A communications standard designed and used to transfer information and documents between servers or from a server to a client. This standard is what enables your Web browser to fetch pages from the World Wide Web. There are several different types of hubs, but in general each receives and sends signals to all the devices connected to it.

When a user clicks on a hyperlink, a page or graphic from the linked location appears in the user's Web browser. Currently IANA manages port numbers 1 through Perhaps the most used ICMP command is ping.

Any message encrypted with that person's public key can then be regarded as being from that person. Network-based intrusion detection systems examine the traffic on a network for signs of unauthorized access or attacks in progress, while host-based systems look at processes running on a local machine for activity an administrator has defined as "bad.

IETF Internet Engineering Task Force A large, open international community of network designers, operators, vendors, and researchers concerned with the evolution of the Internet architecture and the smooth operation of the Internet. IKE first mutually authenticates the two endpoints that plan to set up IPSec tunnels between them; then the endpoints can establish mutually agreed-upon security parameters. See also cipher block chaining. The term sometimes refers to the wires, plugs, and sockets that hardware devices use to communicate with each other.

Other times, it refers to the style in which a software program receives and responds to user input; for example, command line interface or graphical user interface.

Internet address class Historically, to efficiently administer the whole range of possible bit IP addresses, the addresses were separated into three classes that describe networks of varying sizes: A network with a Class A address can have up to about 16 million hosts. A network with a Class B address can have up to 64, hosts.

A network with a Class C address can have up to hosts. Modern addressing techniques favor classless routing, rendering these class categorizations less and less relevant.

For a full discussion of the topic, see the following Security Fundamentals articles: For example, a manufacturer and its key vendors might create an intranet to facilitate managing the process of turning raw materials into finished products. IP Internet Protocol A fundamental set of detailed specifications that controls how data packets are formatted and how they move from one networked computer to another.

IP address An understanding of IP addresses is foundational for managing a network, so we go into some depth with this definition. The devices on the network rely on the address in order to know where to route data.

The format of an IP address is a bit number divided into four 8-bit segments, separated by periods. The four segments, called octets, can be represented in binary notation ones and zeros, the basic building blocks of all software like this: Because writing so many ones and zeros is inefficient and laborious for humans, IP addresses are usually converted to decimal notation when written out but remember, the machines always understand them as ones and zeros.

For example, the same binary address above, expressed in decimal, is In decimal notation, no octet can have a value greater than This is because binary requires 9 ones and zeros to express a number greater than , and the rules for IP addresses only allow 8. Some portion of any IP address designates a network, and the remaining portion of the address designates a specific device on that network. For more information, see network address , Internet address class , and subnet mask.

IP fragments are typically used when an IP packet is too large for the physical media that the data must cross. To send packets larger than 1, bytes over an Ethernet, IP fragments must be used. IP options Extensions to the Internet Protocol used mainly for debugging and for special applications on local networks.

In general, there are no legitimate uses of IP options over an Internet connection. IP options attack A method of gaining unauthorized network access by utilizing IP options. IPSec Internet Protocol Security An open-standard methodology of exchanging data over the public Internet while protecting the data from prying eyes as it travels from the originator to the recipient.

The IETF chartered the IPSec work group to provide cryptographic security services that will flexibly support combinations of authentication, integrity, access control, and confidentiality. IP spoofing The act of inserting a false but ordinary-seeming sender IP address into the "From" field of an Internet transmission's header in order to hide the actual origin of the transmission.

There are few, if any, legitimate reasons to perform IP spoofing; the technique is usually one aspect of an attack. Defines the procedures for authenticating, creating and managing security associations, generating keys, and using digital certificates when establishing VPN connections. ISO International Organization for Standardization An international organization composed of national standards bodies from over 75 countries.

ISO has defined a number of important computer standards, the most significant of which is perhaps OSI Open Systems Interconnection , a standardized architecture for designing networks. A government bureau or an educational institution may be the ISP for some organizations. IV See initialization vector.

J Java applet A small program written in the Java programming language that can be included on an HTML page, much in the same way an image is included. When someone uses a Java-enabled browser to view a page that contains an applet, the applet's code is transferred to that user's system and executed by the browser's Java virtual machine JVM.

For example, if you access a Web page that shows a virtual stock ticker streaming by with live data, that might be enabled by a Java applet. K Kerberos A trusted third-party authentication protocol developed at Massachusetts Institute of Technology and used widely in the United States.

Unlike other authentication schemes, Kerberos does not use public key technology. Instead, it uses symmetric ciphers and secrets shared between the Kerberos server and each individual user. Each user has a unique password, and the Kerberos server uses this password to encrypt messages sent to that user, so the message can't be read by anyone else.

If a message encrypted by a key must be decrypted by using the same key, the key is called a symmetric key. If a message encrypted by a key must be decrypted using a different key, the keys are called asymmetric keys , or a key pair. Key pairs usually comprised of a public key and a private key form the basis of public key cryptography. Two key pairs can have the same user ID, but they have different key IDs.

See also key and key fingerprint. One of the keys is made known publicly, while the other is kept private. The two, together, form a key pair. See also key and keyring. Each user has two types of keyrings: People who wish to receive encrypted messages typically publish their public keys in directories or make their keys otherwise available.

To send them an encrypted message, all you have to do is get a copy of their public key, use the public key to encrypt your message, and send it to them. The only person who can decrypt the message is the person who possesses the matching private key. A designated number of users must bring their shares of the key together to use the key.

L LAN local area network A computer network that spans a relatively small area, generally confined to a single building or group of buildings. LDAP Lightweight Directory Access Protocol A protocol that helps manage information about authorized users on a network such as names, phone numbers, addresses, and what a user is and is not allowed to access.

LDAP is vendor- and platform-neutral, working across otherwise incompatible systems. LED light-emitting diode A small indicator light on a networking device that indicates status and other information about the device. This convention, which all Internet-aware applications expect and utilize, has a variety of purposes, including routing and application testing. M MAC Machine Authentication Code A way to check the integrity of information transmitted over, or stored on, an unreliable medium, based on a secret key.

Typically, MACs are used between two parties who share a secret key, in order to validate the information transmitted between the two parties. MAC address Media Access Control One of the two addresses every networked computer has the other being an IP address , a Media Access Control address is a unique bit identifier usually written as 12 hexadecimal characters grouped in pairs e. It is the physical address of a data device, and is used as an aid for routers trying to locate machines on large networks.

See also ARP and Ethernet address. In its simplest terms, this is the computer you use to configure and monitor a WatchGuard Firebox. MD2 Message Digest 2 bit, one-way hash function that is dependent on a random permutation of bytes. MD2 is considered very secure, but takes a long time to compute, and therefore is rarely used.

See also message digest. MD4 Message Digest 4 A bit, one-way hash function that uses a simple set of bit manipulations on bit operands, developed as a weaker but faster alternative to MD2. Although now widely used, MD5 contains a few flaws discovered in making it slightly weaker, so it is gradually falling out of favor in deference to another message digest function known as SHA Message digests are also known as one-way hash functions because they produce results where it is mathematically infeasible to try to calculate the original message by computing backwards from the result.

Message digest functions are designed so that a change to a single character in the message will cause the message to result in a very different message digest number. Many different message digest functions have been proposed and are now in use; most are considered highly resistant to attack. Many e-mail clients now support MIME, which enables them to send and receive graphics, audio, and video files via the Internet mail system. MIME content types are expressed as a type and a subtype, separated by a slash.

N name resolution The successful look-up of an IP address to discover the name of the networked computer it indicates. Then the Firebox translates that request from the outside world and sends it to the appropriate IP address inside your network.

In this way, the Firebox can hide from outsiders the IP addresses of machines on your internal network. Some people use the term NAT interchangeably with masquerading. For a Class A network, the network address is the first byte of the IP address e. For a class B network, the network address is the first two bytes of the IP address e.

For a class C network, the network address is the first three bytes of the IP address e. In each case, the remaining bits can be used to identify specific computers, often called hosts.

In the Internet, assigned network addresses are globally unique; that is, a computer cannot have the same IP address as any other computer with which it can communicate. Network Configuration wizard Automated software presenting a series of windows.

The various windows and fields prompt you for essential information that helps create a basic Firebox configuration. Every computer attached to a network must have a NIC.

Dividing an Ethernet into multiple segments is a common way of increasing available bandwidth on the individual segments. NFS allows all network users to access shared files stored on computers of different types. A user can manipulate shared files as if the files were stored locally on the user's own hard disk. NFS is typically found on Unix computers. Part of NIST's charter is to distribute complete and accurate information about computer security issues to government and the general public.

Properly configured, NTP can usually keep the clocks of participating hosts within a few milliseconds of each other. Used instead of "byte" in most IP documents because historically many hosts did not use 8-bit bytes. Widely used in World War II, the method consisted of using the key on a page exactly once, then tearing off the page and using the key on the next page for the next message.

Since the key changes with every message, the enemy does not have a feasible chance to decrypt any given message; thus, one-time pads are considered the only perfect encryption scheme -- as long as the bad guys don't intercept a copy of the pad. See hash and message digest. The reason for doing so is that potentially, a larger group of programmers will produce a more useful and bug-free product than a smaller group of programmers, and that more people will use software that is free.

One of the most famous examples of open source software is Linux. Optional interface The Ethernet port on the Firebox provided so you can connect a second secured network. This second network is often referred to as the "demilitarized zone" DMZ , or the Optional network. Optional network A network architecture used by an organization that wants to host its own Internet services without allowing unauthorized access to its private network.

Access from the Optional network to the Trusted network can then be appropriately restricted by the firewall. For that reason, some refer to the Optional network as a "semi-public" network. OOB is very useful for remotely configuring a Firebox when Ethernet access is unavailable. P packet A unit of information formatted according to specific protocols that allow precise transmittal of data from one node in a network to another.

Also called a datagram or a data packet, it contains two parts: The header is like an envelope; the payload is the contents. In Internet Protocol, any message that is larger than 1, bytes gets fragmented into packets for transmission.

A packet filter allows or denies packets depending on where they are going, from whom they are sent, or what port they use. Packet filtering is one technique, among many, for implementing security firewalls.

PAP Password Authentication Protocol An identity verification method used to send a user name and password over a network to a computer that compares the user name and password to a table listing authorized users. WatchGuard products do not support this authentication method because the user name and password travel as clear text that a hacker could read.

The function either uses the parameter in its task, or performs an operation on the parameter. A parameter can be a value such as a number, a name, or even a file. For instance, a function that alphabetizes might not know what text file to alphabetize unless a file name is passed to the function as a parameter. The function might not know whether to print the alphabetized list, display it on a screen, or save it as a new file unless one of those options is also expressed as a parameter.

A parameter can also be referred to as an argument. WatchGuard recommends the use of passphrases in place of passwords. Using P2P client software, a client can receive files from another client. Some P2P file distribution systems require a centralized database of available files such as Napster , while other distribution systems like Gnutella are decentralized. In a common phishing attack, the attacker tries to steal authentication credentials using a fake login form on a malicious website which is designed to look like an actual organization.

Attackers can also send phishing emails to users trying to trick them into downloading attached malware or visiting malicious links. To initiate the VPN Tunnel, we need to force one packet to traverse the VPN and this can be achieved by pinging from one router to another. There is however one caveat that was mentioned in the beginning of this article: The reason for this is simple and logical.

Packet sent with a source address of The time required to bring up the VPN Tunnel is sometimes slightly more than 2 seconds, causing the first ping to timeout. To verify the VPN Tunnel, use the show crypto session command:.

Again, the first ping received a timeout, but the rest received a reply, as expected. Issuing the show crypto session command at the headquarter router will reveal all remote routers public IP addresses. This is usually a good shortcut when trying to figure out the public IP address of your remote routers. Back to Cisco Routers Section. Deal with bandwidth spikes Free Download. Network Analyzer Free Download. Web Vulnerability Scanner Free Download. Pre-share - Use Pre-shared key as the authentication method.

Expressed in either kilobytes after x-amount of traffic, change the key or seconds.

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Configuring Cisco Site to Site IPSec VPN with Dynamic IP Endpoint Cisco Routers. Written by Administrator. Posted in Cisco Routers - Configuring Cisco Routers. IP Intelligence is a service that determines how likely an IP address is a proxy / VPN / bad IP using advanced mathematical and modern computing techniques. A virtual private network (VPN) extends a private network across a public network, and enables users to send and receive data across shared or public networks as if their computing devices were directly connected to the private network. Applications running across a VPN may therefore benefit from the functionality, security, and management .