slides15 Flashcards
what does it mean that a packet contains IP addresses that, say, will be used to set up new connections?
I have no fucking clue
when do problems arise for NAT?
when a packet contains IP addresses that, say, will be used to set up new connections
Simple Service Discovery Protocol
The Simple Service Discovery Protocol (SSDP) is a network protocol based on the Internet Protocol Suite for advertisement and discovery of network services and presence information. It accomplishes this without assistance of server-based configuration mechanisms, such as DHCP or DNS, and without special static configuration of a network host. SSDP is the basis of the discovery protocol of Universal Plug and Play (UPnP) and is intended for use in residential or small office environments.
used for DDOS attacks
Universal Plug and Play
Universal Plug and Play (UPnP) is a set of networking protocols that permits networked devices, such as personal computers, printers, Internet gateways, Wi-Fi access points and mobile devices to seamlessly discover each other’s presence on the network and establish functional network services for data sharing, communications, and entertainment. UPnP is intended primarily for residential networks without enterprise-class devices.
SSDP vulnerability
In 2014 it was discovered that SSDP was being used in DDoS attacks known as an SSDP reflection attack with amplification. Many devices, including some residential routers, have a vulnerability in the UPnP software that allows an attacker to get replies from port number 1900 to a destination address of their choice. With a botnet of thousands of devices the attackers can generate sufficient packet rates and occupy bandwidth to saturate links, causing the denial of service.[7] [8] [9]
Carrier grade NAT
NAT done in the ISP rather than by the end-user
wtf is 100.64.0.0/10
Private network Shared address space[3] for communications between a service provider and its subscribers when using a carrier-grade NAT.
FTP
The File Transfer (‘FTP) is a standard network protocol used for the transfer of computer files between a client and server on a computer network.
FTP is built on a client-server model architecture using separate control and data connections between the client and the server.[1] FTP users may authenticate themselves with a clear-text sign-in protocol, normally in the form of a username and password, but can connect anonymously if the server is configured to allow it. For secure transmission that protects the username and password, and encrypts the content, FTP is often secured with SSL/TLS (FTPS) or replaced with SSH File Transfer Protocol (SFTP).
nat problems
• Complexity in the gateway software
• Scalability problems in the gateway tracking large numbers
of connections
• Bad interactions with some protocols
• Difficulty of making end-to-end connections when both ends are behind a NAT gateway (e.g., Skype, SIP)
• Loss of “an IP address identifies a host uniquely” (a problem for law enforcement)
port forwarding
In computer networking, port forwarding or port mapping is an application of network address translation (NAT) that redirects a communication request from one address and port number combination to another while the packets are traversing a network gateway, such as a router or firewall. This technique is most commonly used to make services on a host residing on a protected or masqueraded (internal) network available to hosts on the opposite side of the gateway (external network), by remapping the destination IP address and port number of the communication to an internal host.[1][2]
STUN
It provides a tool for hosts to discover the presence of a network address translator, and to discover the mapped, usually public, Internet Protocol (IP) address and port number that the NAT has allocated for the application’s User Datagram Protocol (UDP) flows to remote hosts. The protocol requires assistance from a third-party network server (STUN server)
for video/messaging/interactive applications
IPv5
meant for streaming
With the development of IPv6 happening and its promise of nearly unlimited IP addresses and a kind of fresh start for the protocol, IPv5 itself was never transitioned to public use in large part because of its 32-bit limitations.
IPv1, 2, & 3
IPv1, 2, & 3 would be part of the TCP/IP protocols, of which there were 3 versions before the IP protocol was split of of it. IPv4 is actualy the first version of the IP protocol. IPv5 is an experimental TCP/IP protocol called the Internet Stream Protocol that never really went anywhere because increases in badwith made streaming over IPv4 feasible. So IPv5 was never finalized and they skiped to IPv6.
aim of IPv6
- have a larger address space
- reduce the size of router tables
- simplify the protocol so routers can process packets faster • provide security and authentication
- pay proper attention to type of service (DS)
- have better multicasting support
- have mobile hosts with fixed IP addresses
- allow room for evolution of the protocol
- permit IPv4 and IPv6 to coexist during the transition
IPv6
4 bits. The number 6. This is identical in position to IPv4 and can be used to distinguish packets in mixed-version environments. In an Ethernet frame, IPv4 has protocol number 0800, while IPv6 is 86DD, but remember you might be using a different physical layer that does not give the type of its data
