Manage Device Security
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S350 Series 8-Port Gigabit Ethernet Smart Managed Pro Switch Models GS308T and GS310TP
• Fragments. Either select the Enable radio button to allow initial fragments (that is,
the fragment bit is asserted) or leave the default Disable radio button selected to
prevent initial fragments from being used.
This option is not valid for rules that match L4 information such as a TCP port number,
because that information is carried in the initial packet.
• Service Type. Select a service type match condition for the extended IP ACL rule.
The possible options are IP DSCP, IP precedence, and IP TOS, which are alternative
methods to specify a match criterion for the same service type field in the IP header.
Each method uses a different user notation. After you make a selection, you can
specify the appropriate values:
- IP DSCP. This is an optional configuration. Specify the IP DiffServ Code Point
(DSCP) field. The DSCP is defined as the high-order 6 bits of the service type
octet in the IP header. Enter an integer from 0 to 63. To select the IP DSCP, select
one of the DSCP keywords from the menu. To specify a numeric value, select
Other and a field displays in which you can enter numeric value of the DSCP.
- IP Precedence. This is an optional configuration. The IP precedence field in a
packet is defined as the high-order 3 bits of the service type octet in the IP header.
Enter a number from 0 to 7.
- IP TOS. This is an optional configuration. The IP ToS field in a packet is defined
as all 8 bits of the service type octet in the IP header. The ToS bits value is a
hexadecimal number that is composed of numbers 00 to 09 and AA to FF. The
ToS mask value is a hexadecimal number that is composed of numbers 00 to FF.
The ToS mask denotes the bit positions in the ToS bits value that are used for
comparison against the IP ToS field in a packet.
For example, to check for an IP ToS value for which bit 7 is set and is the most
significant value, for which bit 5 is set, and for which bit 1 is cleared, use a ToS
bits value of 0xA0 and a ToS mask of 0xFF.
9. Click the Apply button.
Your settings are saved.
Modify the Match Criteria for an Extended IP ACL Rule
 To modify the match criteria for an existing extended IP ACL rule:
1. Connect your computer to the same network as the switch.
You can use a WiFi or wired connection to connect your computer to the network, or
connect directly to a switch that is off-network using an Ethernet cable.
2. Launch a web browser.
3. In the address field of your web browser, enter the IP address of the switch.
If you do not know the IP address of the switch, see Change the Default IP Address of the
Switch on page 11.