642-813J Free Dumps Study Materials

Question 3: 展示を参照して ください。
攻撃者はス゗ッチ A-SW2 上の Fa0/11 の゗ン ターフェ゗スに接続され、man-in-the-middle 攻
撃のために DHCP サーバーを確立しようとしています。 次のどの勧告はこのタ゗プの攻撃を
緩和しますか。
A. ビルゕクセスブロック内のすべてのス゗ッチポートは DHCP 信頼できるポートとして設
定する必要があります。
B. ビルゕクセスブロ ック内のすべてのス゗ ッチポートは DHCP 信頼できないポートと して
設定する必要があります。
C. ビルゕクセスブロ ック内のホストに接続 するすべてのス゗ッチ ポートは DHCP 信頼 でき
るポートとして設定する必要があります。
D. ビルゕクセスブロ ック内のホストに接続するす べてのス゗ッチポートは DHCP 信頼 でき
ないポートとして設定する必要があります。
E. サーバーフゔーム ブロック内の すべての ス゗ッチポー トは DHCP 信頼できな いポー トと
して設定する必要があります。
F. サー バ ーフ ゔー ムブロ ッ ク内 のサ ーバ ー に接 続 する すべ ての ス ゗ッ チ ポー トは DHCP 信
頼できないポートとして設定する必要があります。
Correct Answer: D
Explanation:
One of the ways that an attacker can gain access to network traffic is to spoof responses that would
be sent by a valid DHCP server. The DHCP spoofing device replies to client DHCP requests. The
legitimate server may reply also, but if the spoofing device is on the same segment as the client, its
reply to the client may arrive first. The intruder's DHCP reply offers an IP address and supporting
information that designates the intruder as the default gateway or Domain Name System (DNS)
server. In the case of a gateway, the clients will then forward packets to the attacking device, which
will in turn send them to the desired destination. This is referred to as a "man-in-the-middle" attack,
and it may go entirely undetected as the intruder intercepts the data flow through the network.
Untrusted ports are those that are not explicitly configured as trusted. A DHCP binding table is built
for untrusted ports. Each entry contains the client MAC address, IP address, lease time, binding type,
VLAN number, and port ID recorded as clients make DHCP requests. The table is then used to filter
subsequent DHCP traffic. From a DHCP snooping perspective, untrusted access ports should not
send any DHCP server responses, such as DHCPOFFER, DHCPACK, DHCPNAK.
Reference: Understanding and Configuring DHCP Snooping
(http://www.cisco.com/en/US/docs/switches/lan/catalyst4500/12.1 /13ew/configuration/guide/dhc
p. html)

Wednesday

642-813日本語 foundation learning gu.rar

Close to 100% passing rate is the best gift that our customers give us. We also hope our 642-813日本語 foundation learning gu.rar exam materials can help more ambitious people pass 642-813日本語 foundation learning gu.rar exam. Our professional team checks the update of every exam materials every day, so please rest assured that the 642-813日本語 foundation learning gu.rar exam software you are using must contain the latest and most information. …

read more

Monday

642-813日本語 dumps

When people take the subway staring blankly, you can use Pad or cell phone to see the PDF version of the 642-813日本語 dumps study materials. While others are playing games online, you can do online 642-813日本語 dumps exam questions. We are sure that as you hard as you are, you can pass 642-813日本語 dumps exam easily in a very short time. While others are surprised at your achievement, you might have found a better job. …

read more

Friday

642-813日本語 switch book pdf

642-813日本語 switch book pdf exam certification is an international recognition, which is equivalent to a passport to enter a higher position. The 642-813日本語 switch book pdf exam materials and test software provided by our Free Dumps are developed by experienced IT experts, which have been updated again and again. Now you just take dozens of Euro to have such reliable 642-813日本語 switch book pdf test materials. Once you get the certification you may have a higher position and salary. …

read more