Method for indicating routing capacity related data or routing delay related data by means of signalling messages in a core network of a telecommunications network using Diameter messages of a Diameter protocol, wherein the core network comprises a first Diameter enabled network node, a second Diameter enabled network node, and at least a third Diameter enabled network node and a fourth Diameter enabled network node, wherein - according to a first routing alternative - a target network node is able to be accessed, by the first Diameter enabled network node, via the third Diameter enabled network node, and - according to a second routing alternative - the target network node or a further target network node is able to be accessed, by the first Diameter enabled network node, via the fourth Diameter enabled network node, the method comprises the following steps: -- a first piece of routing capacity related information is transmitted from the first Diameter enabled network node to the second Diameter enabled network node, and -- a second piece of routing capacity related information is transmitted from the first Diameter enabled network node to the second Diameter enabled network node, wherein the first and second piece of routing capacity related information (331, 331') is transmitted by at least one Diameter message (302, 304), wherein the first piece of routing capacity related information comprises aggregated routing capacity data or aggregated routing delay data related to the first routing alternative, and wherein the second piece of routing capacity related information comprises aggregated routing capacity data or aggregated routing delay data related to the second routing alternative, wherein the first piece of routing capacity related information is transmitted by the at least one Diameter message (302, 304) by means of at least a first Attribute-Value-Pair and/or wherein the second piece of routing capacity related information is transmitted by the at least one Diameter message (302, 304) by means of at least a second Attribute-Value-Pair, wherein the first piece of routing capacity related information, and/or the second piece of routing capacity related information indicates an overload situation of at least one of the first, third or fourth network node (32, 31, 31'), wherein the first piece of routing capacity related information and the second piece of routing capacity related information, respectively, indicates one or a plurality out of the following: -- the number of estimated requests per a predefined time interval or the rate of estimated requests that the respective routing alternative is able to bear, -- the estimated occupied load ratio that the respective routing alternative has to bear, -- the estimated unoccupied load ratio that the respective routing alternative is able to bear, -- the estimated delay that it takes on the respective routing alternative to process the request by the target network node or the further target network node, respectively. -- a first piece of routing capacity related information is transmitted from the first Diameter enabled network node to the second Diameter enabled network node, and -- a second piece of routing capacity related information is transmitted from the first Diameter enabled network node to the second Diameter enabled network node, -- the number of estimated requests per a predefined time interval or the rate of estimated requests that the respective routing alternative is able to bear, -- the estimated occupied load ratio that the respective routing alternative has to bear, -- the estimated unoccupied load ratio that the respective routing alternative is able to bear, -- the estimated delay that it takes on the respective routing alternative to process the request by the target network node or the further target network node, respectively.