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Using the Anomaly Drops graphs

Using the Anomaly Drops graphs

Use the Anomaly Drops graphs to monitor drops due to Layer 3, Layer 4, and Layer 7 anomalies.

Customize the graph with the following viewing parameters: SPP, Reporting Period (1-hr to 1-yr), Linear/Logarithmic Y-Axis.

Placing the cursor on the Monitor graph will display a tool-tip with additional information.

Before you begin:

  • You must have Read permission for the Monitor menu.
  • Refer to Reading Monitor graphs to understand the graphs in detail.
To display the graph:
  1. Go to Monitor > Drops Monitor > SPP > Anomaly Drops Tab > [SPP] [Aggregate/Layer 3/4/7] [Y-Axis View] [Reporting Period].

Statistic

Description

Aggregate

Aggregation of all anomaly drops for:

  • Layer 3
  • Layer 4
  • Layer 7

Layer 3

Drops due to (IP Profile Strict Anomalies option):

  • IP Header Checksum Error
  • Source and Destination Address Match - Source and Destination addresses are the same (LAND attack).

  • Source/Destination as LocalHost - Source or Destination address is the same as the localhost (loopback address spoofing).

  • Drops due to the other Layer 3 anomalies, including:
    • IP version other than 4 or 6
    • Header length less than 5 words
    • End of packet (EOP) before 20 bytes of IPV4 Data
    • Total length less than 20 bytes
    • EOP comes before the length specified by Total length
    • End of Header before the data offset (while parsing options)
    • Length field in LSRR/SSRR option is other than (3+(n*4)) where n takes value greater than or equal to 1
    • Pointer in LSRR/SSRR is other than (n*4) where n takes value greater than or equal to 1
    • For IP Options length less than 3
    • Reserved flag set
    • More fragments and Don't Fragment Flags both set

Layer 4

Aggregate

Aggregate graphs showing all anomaly drops due to Layer 4:

  • Header
  • State

Header

Anomaly drops due to (IP and TCP Profile Strict Anomalies options):

  • TCP checksum errors
  • UDP checksum errors
  • ICMP Checksum errors
  • TCP Invalid Flag Combination –Invalid TCP flag combinations such as SYN-PSH-RST
  • (other) Anomaly Detected, including:
    • Other header anomalies, such as incomplete packet
    • Urgent flag is set then the urgent pointer must be non-zero
    • SYN or FIN or RST is set for fragmented packets
    • Data offset is less than 5 for a TCP packet
    • End of packet is detected before the 20 bytes of TCP header
    • EOP before the data offset indicated data offset
    • Length field in Window scale option other than 3 in a TCP packet
    • Missing UDP payload
    • Missing ICMP payload
    • SYN with payload (TCP Profile option)
  • Invalid ICMPv4 Type/Code via Protocol 1 (ICMP Profile option) – Invalidates (makes anomalies) the >64,000 available ICMP Types/Codes that are not IETF/IANA ratified and in-use.
  • Invalid ICMPv6 Type/Code via Protocol 58 (ICMP Profile option) – Invalidates (makes anomalies) the >64,000 available ICMP Types/Codes that are not IETF/IANA ratified and in-use.

State

Anomaly drops due to (TCP Profile options):

  • Foreign Packets (Out-of-State) – (TCP Profile Foreign Packet Validation option)
  • Forward Transmission Not Within Window - Packets outside the receiver’s windows (TCP Profile Sequence Validation option)
  • Reverse Transmission Not Within Window - Packets outside the receiver’s windows (TCP Profile Sequence Validation option)
  • TCP State Transition - Packets that violate the TCP Protocol state transition rules or sequence numbers (TCP Profile State Transition Validation option)
  • Foreign Packets (Aggressive aging and Slow Connections) – Packets no longer in active sessions due to aggressive aging or slow connection blocking (TCP Profile option)
  • Aggressive Aging (Concurrent Connection per Source Flood) - Packets no longer in active sessions due to aggressive aging based on Concurrent Connections per Source Threshold and Aggressive Aging Feature Control > High Concurrent Connection per Source (TCP Profile option)

Layer 7

Aggregate

Aggregate of drops due to anomalies for:

  • HTTP
  • SSL
  • DNS
  • NTP
  • DTLS
  • QUIC

HTTP Header

HTTP Anomaly Drops (HTTP Profile options) for:

  • Known Method - Drops packets if the METHOD matches with any of the eight known OpCodes selected as not allowed in the HTTP Profile (GET, HEAD, OPTIONS, TRACE, POST, PUT, DELETE, CONNECT)
  • Unknown Method – Drops packets whose METHOD is outside the 8 known Methods (any Method that is not: GET, HEAD, OPTIONS, TRACE, POST, PUT, DELETE, CONNECT)
  • Invalid HTTP Version - packets with an invalid HTTP version
  • Range Present - packets with a header range request
  • Incomplete HTTP Request - HTTP requests that do not end in the correct end-of-packet information.

SSL

SSL/TLS Anomaly Drops (SSL/TLS Profile options) for:

  • SSL Renegotiation – packets dropped due to excessive numbers of renegotiation requests over time as configured in the SSL/TLS Profile
  • SSL Protocol errors
  • SSL Version errors
  • SSL Cipher suite errors
  • SSL Incomplete Request errors

DNS

DNS Anomaly Drops (DNS Profile Options) for:

  • Header
  • Query
  • Response
  • Buffer Overflow
  • Exploit
  • Info
  • Data

NTP

NTP Anomaly Drops (NTP Profile Options) for:

  • Header
  • State

DTLS

DTLS Anomaly Drops for:

  • State (DTLS Profile: Protocol option)

QUIC

QUIC Anomaly Drops for:

  • Strict (QUIC Profile: Strict Anomalies Check)

  • Initial Packet Size (QUIC Profile: Initial Packet Check)

  • Version (QUIC Profile: Version Check)

Using the Anomaly Drops graphs

Using the Anomaly Drops graphs

Use the Anomaly Drops graphs to monitor drops due to Layer 3, Layer 4, and Layer 7 anomalies.

Customize the graph with the following viewing parameters: SPP, Reporting Period (1-hr to 1-yr), Linear/Logarithmic Y-Axis.

Placing the cursor on the Monitor graph will display a tool-tip with additional information.

Before you begin:

  • You must have Read permission for the Monitor menu.
  • Refer to Reading Monitor graphs to understand the graphs in detail.
To display the graph:
  1. Go to Monitor > Drops Monitor > SPP > Anomaly Drops Tab > [SPP] [Aggregate/Layer 3/4/7] [Y-Axis View] [Reporting Period].

Statistic

Description

Aggregate

Aggregation of all anomaly drops for:

  • Layer 3
  • Layer 4
  • Layer 7

Layer 3

Drops due to (IP Profile Strict Anomalies option):

  • IP Header Checksum Error
  • Source and Destination Address Match - Source and Destination addresses are the same (LAND attack).

  • Source/Destination as LocalHost - Source or Destination address is the same as the localhost (loopback address spoofing).

  • Drops due to the other Layer 3 anomalies, including:
    • IP version other than 4 or 6
    • Header length less than 5 words
    • End of packet (EOP) before 20 bytes of IPV4 Data
    • Total length less than 20 bytes
    • EOP comes before the length specified by Total length
    • End of Header before the data offset (while parsing options)
    • Length field in LSRR/SSRR option is other than (3+(n*4)) where n takes value greater than or equal to 1
    • Pointer in LSRR/SSRR is other than (n*4) where n takes value greater than or equal to 1
    • For IP Options length less than 3
    • Reserved flag set
    • More fragments and Don't Fragment Flags both set

Layer 4

Aggregate

Aggregate graphs showing all anomaly drops due to Layer 4:

  • Header
  • State

Header

Anomaly drops due to (IP and TCP Profile Strict Anomalies options):

  • TCP checksum errors
  • UDP checksum errors
  • ICMP Checksum errors
  • TCP Invalid Flag Combination –Invalid TCP flag combinations such as SYN-PSH-RST
  • (other) Anomaly Detected, including:
    • Other header anomalies, such as incomplete packet
    • Urgent flag is set then the urgent pointer must be non-zero
    • SYN or FIN or RST is set for fragmented packets
    • Data offset is less than 5 for a TCP packet
    • End of packet is detected before the 20 bytes of TCP header
    • EOP before the data offset indicated data offset
    • Length field in Window scale option other than 3 in a TCP packet
    • Missing UDP payload
    • Missing ICMP payload
    • SYN with payload (TCP Profile option)
  • Invalid ICMPv4 Type/Code via Protocol 1 (ICMP Profile option) – Invalidates (makes anomalies) the >64,000 available ICMP Types/Codes that are not IETF/IANA ratified and in-use.
  • Invalid ICMPv6 Type/Code via Protocol 58 (ICMP Profile option) – Invalidates (makes anomalies) the >64,000 available ICMP Types/Codes that are not IETF/IANA ratified and in-use.

State

Anomaly drops due to (TCP Profile options):

  • Foreign Packets (Out-of-State) – (TCP Profile Foreign Packet Validation option)
  • Forward Transmission Not Within Window - Packets outside the receiver’s windows (TCP Profile Sequence Validation option)
  • Reverse Transmission Not Within Window - Packets outside the receiver’s windows (TCP Profile Sequence Validation option)
  • TCP State Transition - Packets that violate the TCP Protocol state transition rules or sequence numbers (TCP Profile State Transition Validation option)
  • Foreign Packets (Aggressive aging and Slow Connections) – Packets no longer in active sessions due to aggressive aging or slow connection blocking (TCP Profile option)
  • Aggressive Aging (Concurrent Connection per Source Flood) - Packets no longer in active sessions due to aggressive aging based on Concurrent Connections per Source Threshold and Aggressive Aging Feature Control > High Concurrent Connection per Source (TCP Profile option)

Layer 7

Aggregate

Aggregate of drops due to anomalies for:

  • HTTP
  • SSL
  • DNS
  • NTP
  • DTLS
  • QUIC

HTTP Header

HTTP Anomaly Drops (HTTP Profile options) for:

  • Known Method - Drops packets if the METHOD matches with any of the eight known OpCodes selected as not allowed in the HTTP Profile (GET, HEAD, OPTIONS, TRACE, POST, PUT, DELETE, CONNECT)
  • Unknown Method – Drops packets whose METHOD is outside the 8 known Methods (any Method that is not: GET, HEAD, OPTIONS, TRACE, POST, PUT, DELETE, CONNECT)
  • Invalid HTTP Version - packets with an invalid HTTP version
  • Range Present - packets with a header range request
  • Incomplete HTTP Request - HTTP requests that do not end in the correct end-of-packet information.

SSL

SSL/TLS Anomaly Drops (SSL/TLS Profile options) for:

  • SSL Renegotiation – packets dropped due to excessive numbers of renegotiation requests over time as configured in the SSL/TLS Profile
  • SSL Protocol errors
  • SSL Version errors
  • SSL Cipher suite errors
  • SSL Incomplete Request errors

DNS

DNS Anomaly Drops (DNS Profile Options) for:

  • Header
  • Query
  • Response
  • Buffer Overflow
  • Exploit
  • Info
  • Data

NTP

NTP Anomaly Drops (NTP Profile Options) for:

  • Header
  • State

DTLS

DTLS Anomaly Drops for:

  • State (DTLS Profile: Protocol option)

QUIC

QUIC Anomaly Drops for:

  • Strict (QUIC Profile: Strict Anomalies Check)

  • Initial Packet Size (QUIC Profile: Initial Packet Check)

  • Version (QUIC Profile: Version Check)