Denial-of-Service Attacks

Denial-of-service (DoS) attacks attempt to deny valid users access to network or server resources by using up all the resources of the network element or server. By using up all the resources, a malicious user can deny access by valid users.
There are many kinds of DoS attacks. Some can be thwarted by using stateless filtering, while others may require state (flow) information. The following list describes some common DoS attacks:
Synchronization (SYN) flood—Attempting to create a large number of Transmission Control Protocol (TCP) connections by sending synchronization packets but not completing the connections. Known as half-open connections, these incomplete SYN packets take some time to be removed. Because servers often have a limit on the number of connections allowed, this type of attack denies service to valid users.
Internet Control Message Protocol (ICMP) or User Datagram Protocol (UDP) flood—Preventing access to a network or host with a flood of either UDP or ICMP packets above that which the network elements can handle.
Ping of death—Sending very large and fragmented ICMP packets that may cause some IP stacks to crash.
Land attack—Sending TCP SYN packets with the source and destination address set to the address of the machine being attacked.
Teardrop—Sending the first and second part of a TCP packet in different IP fragments with overlapping offsets, causing the target host to crash.
IP source route attack—Using the source route option, an attacker can masquerade as a trusted host.
IP multicast source—Using a multicast source to cause a response that consumes network resources.
TCP state machine attacks—Setting both the SYN and finish (FIN) bits or the FIN bit with no acknowledgment (ACK) bit within TCP packets.
Other UDP issues—Sending a UDP echo to an IP broadcast destination addresses (called a fraggle attack) consumes network resources (because all hosts on the subnetwork respond). Sending a UDP packet in which the UDP length is less than the IP length can cause some systems to crash.

CRM 4.0 customizations for improving performance

Organizations may need to use MS Dynamics CRM in WAN environment where performance is a big issue. To run MS Dynamics CRM in WAN environment, we should remember some tips and tricks.

The following tasks should be done:

1. Customized the Account and Contact forms
--Disabled Forms Assistant
--Changed the Default Public View to display two fields
--Removed selected fields and search fields
2. Changed Number of Fields returned to 25
3. Specified to show only Sales in Workplace Pane
4. Changed the security role to only allow the Contact and Account Entities
5. Disabled Duplicate Detection
6. Removed as many items as possible from the left Navigation Bar (except Workplace)
7. Customized Accounts and Contacts grid to show only the Name and a few other key fields
8. Removed the majority of items in the left Navigation Bar of the Account and Contact forms

Detail of Customizations

1. Disabled the Forms Assistant
2. Changed the Default Public View to display two fields

3. Removed fields:
 Account form: Other Phone; Fax; Phone; Address2; Address3
 Contact form: Street2; Street3; Country/Region; Phone; Salutation; Middle Name; Home Phone; Fax; Pager

4. Removed search fields:
 Account form: Account Number; E-mail
 Contact form: All except FullName

5. Changed the Number of Fields returned to 25

6. Modified the Workplace Pane to show only Sales

7. Changed the security role to allow only the Contact and Account entities

8. Disabled Duplicate Detection

9. Removed all unnecessary items (except Workplace) from the left Navigation Bar

10. Removed unnecessary items from the left Navigation Bar of the Account/Contact forms.

Common Mistakes for Network Administrators

1. Not changing the default passwords on all network devices.
2. Sharing a password across multiple network devices.
3. Failing to find SQL coding errors.
4. Misconfiguring your access control lists.
5. Allowing nonsecure remote access and management software.
6. Failing to test noncritical applications for basic vulnerabilities.
7. Not adequately protecting your servers from malware.
8. Failing to configure your routers to prohibit unwanted outbound traffic.
9. Not knowing where credit card or other critical customer data is stored.
10. Not following the Payment Card Industry Data Security Standards.

Saint Martin is loosing its charm

Taher Ali

When I visited Saint Martin for the first time, I found that it was the best place for enjoying vacation. At the same time, this was the most beautiful place. To me anyone can go there for thousands time and he will not be bored. But, I was wrong. When I went there for the second time, I found this was a boring journey.
People are also working to reduce the gorgeousness of Saint Martin. All the mobile companies have setup their network and they are actually making obstacles for enjoying leisure. Foods are very expensive than before. At the same time, the quality also deteriorated. You will not get any place to enjoy your leisure. How sad!

However, it was nice with having friends and colleagues around. All the peoples were very funny. I have to mention one name 'The Jacks Bhai'. He gave a very enjoying session at the hotel room when all of us were very tired. Everyone will remember this for .........