In 7.2.2.2.3.1 General, we have:
"The algorithm and nonce length used of the UADP NetworkMessage security depend on the selected SecurityPolicy. They are defined by SymmetricPubSubEncryptionAlgorithm and SymmetricPubSubNonceLength."

There are several issues here.

As far as I can tell, the name SymmetricPubSubEncryptionAlgorithm is not anywhere else in the spec, including Part 7.

In addition, it probably should correspond to what is used in Table 74, but that table, "SymmetricEncryptionAlgorithm" is used (4 occurrences).

I think that we also kind of miss the definition of the contents of the SecurityPolicy. There is Table 35 in Part 6, but that covers Client-Server only.

And, in Part 7, I tried to locate the security policy parameters for this, but was not fully successful either. Hopefully I am looking at the right place. I navigated to Security Category -> Facets -> Security Policy -> SecurityPolicy - PubSub-Aes256-CTR, or SecurityPolicy [A] - PubSub-Aes128-CTR. In them,

1) the encryption algorithm, if that us to derive from the "Name" column in the table appears to be prefixed by "SymmetricEncryptionAlgorithm", and not "SymmetricPubSubEncryptionAlgorithm"

2) the SymmetricPubSubNonceLength is not listed at all. There is a sentence "The input nonce length is 4 bytes." but that's either not correct (because according to Table 75, the nonce length comes to 8 bytes) or it is not the same thing.