Month: October 2012

NetBIOS

Sytek Inc developed NetBIOS in 1983 as an API (a specification proposed for using it as an interface to communicate by software parts) for software contact over IBM PC LAN networking technology. The Network Basic Input/Output System (NetBIOS) was at first introduced by IBM (a company, which is running IT consultation and computer technology business to access LAN resources. Since its creation, NetBIOS has developed as a starting point for a lot of other networking applications including International Business Machines, for example: Sytek (API). This Basic Input/Output system serves as an interface specifications to access the networking services.

How to prevent or stop DoS attacks?

application layer firewallThe response and prevention

In order to defend against Denial of Service attacks the combination of attack detection use is typically involved in it, classification of traffic as well as response tools, and the target is to block traffic if identified as illegal and permit the legal traffic only after identifying it. Below is a list of response tools as well as prevention:

Firewalls

The rules of firewalls are quite simple like to permit or not to permit ports, protocols, or IP addresses. There are some DoS attacks that are quite complicated for number of firewalls, for example if an attack occurs on port 80 (web service), it is not easy for the firewalls to differentiate between the bad traffic and the good traffic of DoS attack so the filter packet filter firewalls cannot prevent the attack. In addition, firewalls may be located too deeply in the network. Even before the traffic enters the firewall the affect on routers may take place. However, firewalls can play an effective role in preventing users from the launch of even simple flooding attacks that can occur from the machines behind the firewall.

DoS Methods – PDoS, Permanent DoS attacks

DoSA PDoS or permanent denial-of-service, also referred to as phlashing, is a severe attack that completely damage a system as a result of which the system’s reinstallation of hardware or replacement is required. A PDoS attack exploits the flaws of security which further permits the administration present far away on the hardware of the victim management interfaces, like printers, routers, or other hardware used for networking.

MPLS – Multiprotocol Label Switching

There is so much about MPLS and how MPLS works. Here I wrote some simple introductory lines about it but only from one perspective. The costumer side one. There is nothing here about BGP and all the things that need to be done and configured in order for MPLS to function in ISP cloud. As an introductory in MPLS this text will take you to the central office and branch side of the MPLS configuration and in this way it will be simpler to explain and enter in the world of MPLS networking technology.

MPLS

In MPLS networks, packets are sending with special MPLS prefix before IP packet data. With an MPLS header that is sometimes mentioned as a label stack. In MPLS header there are labels, every label with some value:

  • Traffic-class field, important for quality of service – QoS
  • Bottom-of-stack flag
  • 8-bit time-to-live – TTL field

DoS Methods – ICMP and SYN flood, Teardrop and Low-rate DoS attacks

ICMP flood

Smurf attack is one specific form of a flooding DoS attack that occurs on the public Internet. It solely depends on incorrect configuration network equipments that permit packets that are supposed to be sent to all hosts of computer on a specific network not via any machine but only via network’s broadcast address. Then the network actually works or serves as a smurf amplifier. In an attack like this, the killers or the perpetrators will send IP packets in huge number displaying the fake source address as to show that it is a victim’s address.