Palo Alto Networks, Inc.

Brocade Communications Systems, Inc.

Li Meng

Dhwanit Shah

Zihang Xiao

Charles Bransi

Adoor V Balasubramanian

Mengying Jiang

Xin Yao

Lexuan Sun

Sarveshwar Meta Rao

Soundarya Sivaramakrishnan

Separating awareness of multipart file transmissions of different applications from traffic handling at a granularity of an individual application layer session facilitates efficient cybersecurity enforcement on multipart file transmissions. A protocol-based multipart file transmission regulator ('regulator') determines a per session message handling action to prevent completion of a multipart file transmission based on a protocol of an application identified for the session until cybersecurity analysis can be performed. The regulator then communicates the message handling action to a network component supporting the session. The regulator maintains information and file chunks in a data store for active sessions and determines with the data store whether a condition for requesting cybersecurity analysis for a multipart file transmission is satisfied. Upon obtaining a cybersecurity analysis verdict, the regulator provides the verdict or a verdict based instruction to the network component that ensures the multipart file transmission is compliant with a cybersecurity policy(ies).

Inline inspection cybersecurity enforcement of multipart file transmissions

To reduce overhead generated by maintaining a full mesh network with static spoke-to-spoke tunnels while providing the efficiency of spoke-to-spoke communication, BGP configuration is automated to provide for dynamic establishment of spoke-to-spoke tunnels. A virtual Internet Protocol (VIP) address is assigned to each spoke in the network. Spokes advertises their VIP address to the hub for communication to the other spokes. A spoke sets the route next hop in its routing table for a remote spoke to the VIP of the remote spoke. Establishment of a tunnel between spokes is initiated after detecting data is to be communicated between the spokes while data is temporarily routed through the hub. Data is routed directly to the receiving spoke through the dynamic tunnel once the tunnel is active. Tunnels between spokes are terminated dynamically after a period of inactivity to reduce overhead caused by consistent maintenance of dynamic tunnels with low use.

Dynamic establishment and termination of VPN tunnels between spokes

Leveraging non-transient or persistent device identifiers to enforce device quarantine instead of IP addresses accommodates the transient associations of IP addresses to devices without compromising the effectiveness of quarantine. When a device has been determined to be compromised and is quarantined, the quarantine of the device is enforced using the IP address of the device. However, IP address assignment is transient. With each connection, a device can be assigned a different IP address. After a connection is established, a gateway can collect a device identifying value(s) that persists across network connections (e.g., host identifier (hostid) and device serial number). With a persistent device identifier, a quarantine list can be enforced in a data/forwarding plane regardless of a compromised device being assigned different network addresses.

Persistent device identifier driven compromised device quarantine

A solution for tunnel path MTU discovery includes, at a first network device configured as an origination endpoint for a tunnel, storing a keep-alive packet having a size of an interface maximum transmission unit (MTU), the keep-alive packet indicating the packet should not be fragmented, the second network device configured as a termination endpoint for the tunnel. If the sending fails, the size of the keep-alive packet is iteratively changed to converge upon a path MTU, where the path MTU is the size of a largest keep-alive packet that can be sent from the first network device to the second network device without fragmentation.

Tunnel path MTU discovery

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San Jose, CA, United States of America

Li Meng