C5 Field Guideunofficial

COS · Communication Security

COS-02 Security Requirements for Connections in the Cloud Service Provider's Network

1 sub-criterion

Changed since C5:2020

Basic criterion

Bullet points are now sorted to ease discussions about specific list items.

Wording in C5:2020

Basic criterion

Specific security requirements are designed, published and provided for establishing connections within the Cloud Service Provider's network. The security requirements define for the Cloud Service Provider's area of responsibility:

  • in which cases the security zones are to be separated and in which cases cloud customers are to be logically or physically segregated;
  • which communication relationships and which network and application protocols are permitted in each case;
  • how the data traffic for administration and monitoring is segregated from each on network level;
  • which internal, cross-location communication is permitted and;
  • which cross-network communication is allowed

All changes since C5:2020

Basic criterion

COS-02.01B

Specific security requirements are designed, documented and provided for establishing connections within the cloud service provider's network. The security requirements define for the cloud service provider's area of responsibility:

  1. In which cases the security zones are to be separated and in which cases cloud service customers are to be logically or physically separated;
  2. Which communication relationships and which network and application protocols are permitted in each case;
  3. How the data traffic for administration and monitoring is separated from each on network level;
  4. How office networks are secured with firewalls and secure WIFI configurations as well as VPN for remote access;
  5. Which internal, cross-partition communication is permitted; and
  6. Which cross-network communication is allowed.
Supplementary information

Cross-partition communication can be realised for e.g. individual regions or locations via e.g. WAN, LAN, VPN, RAS.

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