The System Hacking Cycle Computer Science

System hacking means to hack system password within the operating system. Many hacking attempts start with attempting to crack passwords. However, passwords are the key piece of information needed to access a system. Users, while creating a password, often select password that are prone to being cracked. Passwords may be cracked manually or with automated tools such as dictionary or brute-force method, each of which are discussed in this paper.

Scanning and enumeration is the first part of ethical hacking and contains the hacker target systems . Enumeration is the follow-on step once scanning is complete and is used to identify computer names, usernames, and shares. Scanning and enumeration are discussed together because many hacking tools perform both.

The system hacking cycle consists of six steps:- a. Enumeration

b. Cracking Passwords c. Escalating Privileges

d. Executing Applications

e. Hiding files

f. Covering tracks

Enumeration occurs after making the IPv4 protocol independent of the physical network, the designers decided to make the maximum length of the IPv4 datagram equal to 65,535 bytes. This makes transmission more efficient if we use a protocol with an MTU of this size. How­ ever, for other physical networks, we must divide the datagram to make it possible to pass through these networks. This is called fragmentation. The source usually does not fragment the IPv4 packet. The transport layer will instead segment the data into a size that can be accommodated by IPv4 and the data link layer in use. When a datagram is fragmented, each fragment has its own header with most of the fields repeated, but with some changed. A fragmented datagram may itself be fragmented if it encounters a network with an even smaller MTU. In other words, a data­gram can be fragmented several times before it reaches the final destination. In IPv4, a datagram can be fragmented by the source host or any router in the path although there is a tendency to limit fragmentation only at the source. The reassembly of the datagram, however, is done only by the destination host because each fragment becomes an independent datagram. Whereas the fragmented datagram can travel through different routes, and we can never control or guarantee which route a fragmented data­ gram may take, all the information is provided by other means such as the hop-by-hop options or other protocols. In its simplest form, a flow label can be used to speed up the processing of a packet by a router. When a router receives a packet, instead of consulting the routing table and going through a routing algorithm to define the address of the next hop, it can easily look in a flow label table for the next hop. In its more sophisticated form, a flow lab

Many hacking attempts can initialize with to attempt crack passwords. Passwords are the important information which is required to login a system. Users, when creating passwords, often select passwords that are difficult to guess.

Passwords are stored in the Security Accounts Manager (SAM) file on a Windows system and in a password shadow file on a Linux system.

Manual Password cracking involves attempting to log on with different passwords. The hacker follows these steps:

1. Find a valid user account for password test.

2. You can create list of possible passwords.

3. Arrange the passwords according to possibility

4. Try each password.

5. Try and try for correct password.

In its simplest form, a flow label can be used to speed up the processing of a packet by a router. When a router receives a packet, instead of consulting the routing table and going through a routing algorithm to define the address of the next hop, it can easily look in a flow label table for the next hop.

In its more sophisticated form, a flow label can be used to support the transmission of real-time audio and video. Real-time audio or video, particularly in digital form, requires resources such as high bandwidth, large buffers, long processing time, and so on. A process can make a reservation for these resources beforehand to guarantee that real-time data will not be delayed due to a lack of resources. The use of real-time data and the reservation of these resources require other protocols such as Real-Time Protocol (RTP) and Resource Reservation Protocol (RSVP) in addition to IPv6.

To allow the effective use of flow labels, three rules have been defined:

1. The flow label is assigned to a packet by the source host. The label is a random number between 1 and 224. A source must not reuse a flow label for a new flow while the existing flow is still active.

2. If a host does not support the flow label, it sets this field to zero. If a router does not support the flow label, it simply ignores it.

3. All packets belonging to the same flow have the same source, same destination, same priority, and same option.

2.